Graphs are drawn as the negative

Error 07 Syntax
Means you made a typing error while entering the equation. Using the minus sign instead of the negation sign (change sign) (-), can produce a syntax error. Maybe you need to explicitly type the multiplication sign
y= (-) 1.5*x +3
Try entering it as 3 - 1.5*x

To have any meaning, the x variable must be in radians.
To find the solutions of this equation you can graph the functions
y_1=x*sin(x)
y_2=0.1
Graph the two functions and find the intersection points of the two.
Because the two functions are even F(-x)=F(x), it suffices to consider their intersections on the interval [0, + infinity[
There are many solutions (an infinite number of them)
See some screen captures below.
After the graphs are drawn, use the G-Solve feature to find the intersections.

After you enter the data draw the SCATTER plot first.
When you perform the (linear) regression analysis LineReg, save the regression equation to a function, for example Y1
The syntax is
LineReg L1, L2, Y1 ENTER


From the Stat>CALC menu press LineReg
The command echoes on command line
Press [2nd][1] to enter the L1 list on command line
Press [,] to separate
Press [2nd] [2] to enter L2 on the command line
Press [,] the comma again
Press [VARS][>][Y-Vars][1~Function][1:Y1] [ENTER]
Press [GRAPH] to have the regression line equation drawn
on the same screen as the Scatter Plot you drew before.

To enter powers of trigonometric functions you must enclose the functions in parentheses and then apply the exponent to the whole. For example X1t =(sin T)^3 , Y1t=(cos T)^3 will give you a shape similar to a rhombus with concave sides. The symbol ^syands for the operation of raising to a power. The key is the one with the caret symbol ^ , and it is wedged between the xsqure and EXIT keys (third row of keys).
As regards the cotangent, use the equivalent definition cot(X)=1/tan(X).

I am sorry but I will have to assume that you know how to enter the data.

Once you enter your data [MENU][STAT], press [F1:Graph], select Gph1, Gph2, or Gph3. Once the graph of the experimental data is drawn, you will have access to the diverse regression models. Your choices are [X:Linear] [Med-Med], [Quadratic :X^2] [Cubic;X^3] [Quartic: X^2]. Press [F6] to scroll right to access the others: [Logarithmic:LOG], [Exponential :EXP], [Power :Pwr] and [Sinusoidal: Sin]

After you select a model and press [EXE], the screen displays the equation and its various coefficients. On that same screen, you have a menu option [F6:Draw]. If you select it, the regression curve will be drawn on the same screen as your statistical graph. This allows you to judge if the fit is good. If it is not, you have the option to choose another model.
The other option [F5:Copy] allows you to save the regression equation in the Y1, Y2, etc. variables.

PS If you do not know how to enter data post a comment to this effect and I will see what I can do to help you.

I am sorry but I will have to assume that you know how to enter the data.

Once you enter your data [MENU][STAT], press [F1:Graph], select Gph1, Gph2, or Gph3. Once the graph of the experimental data is drawn, you will have access to the diverse regression models. Your choices are [X:Linear] [Med-Med], [Quadratic :X^2] [Cubic;X^3] [Quartic: X^2]. Press [F6] to scroll right to access the others: [Logarithmic:LOG], [Exponential :EXP], [Power :Pwr] and [Sinusoidal: Sin]

After you select a model and press [EXE], the screen displays the equation and its various coefficients. On that same screen, you have a menu option [F6:Draw]. If you select it, the regression curve will be drawn on the same screen as your statistical graph. This allows you to judge if the fit is good. If it is not, you have the option to choose another model.
The other option [F5:Copy] allows you to save the regression equation in the Y1, Y2, etc. variables.

PS If you do not know how to enter data post a comment to this effect and I will see what I can do to help you.

Hello,
Your graphic is drawn in dotted style. Change it to connected if you want.
Press [MODE] Use arrow to highlight Connected and press [ENTER]. Press [GRAPH] tor edraw your graph.
Hope it helps

Hello,
I am sorry but I will have to assume that you know how to enter the data.
Once you enter your data [MENU][STAT], press [F1:Graph], select Gph1, Gph2, or Gph3. Once the graph of the experimental data is drawn, you will have access to the diverse regression models. Your choices are [X:Linear] [Med-Med], [Quadratic :X^2] [Cubic;X^3] [Quartic: X^2]. Press [F6] to scroll right to access the others: [Logarithmic:LOG], [Exponential :EXP], [Power :Pwr] and [Sinusoidal: Sin]
After you select a model and press [EXE], the screen displays the equation and its various coefficients. On that same screen, you have a menu option [F6:Draw]. If you select it, the regression curve will be drawn on the same screen as your statistical graph. This allows you to judge if the fit is good. If it is not, you have the option to choose another model.
The other option [F5:Copy] allows you to save the regression equation in the Y1, Y2, etc. variables.

Hope it helps.

Hello,
Once you enter your data [MENU][STAT], press [F1:Graph], select Gph1, Gph2, or Gph3. Once the graph of the experimental data is drawn, you will have access to the diverse regression models. Your choices are [X:Linear] [Med-Med], [Quadratic :X^2] [Cubic;X^3] [Quartic: X^2]. Press [F6] to scroll right to access the others: [Logarithmic:LOG], [Exponential :EXP], [Power :Pwr] and [Sinusoidal: Sin]
After you select a model and press [EXE], the screen displays the equation and its various coefficients. On that same screen, you have a menu option [F6:Draw]. If you select it, the regression curve will be drawn on the same screen as your statistical graph. This allows you to judge if the fit is good. If it is not, you have the option to choose another model.
The other option [F5:Copy] allows you to save the regression equation in the Y1, Y2, etc. variables.

Hope it helps.

Hello,
The marking that so puzzle you define the type of line (or dots) to represent the graphs. Enter as many functions as there are Y variables.
After entering a function press [ENTER] to jump to the next one.
When finished entering all functions press GRAPH. If you want graphs drawn one after the other, in MODE highlight Sequential (6th line) and press ENTER. If you want graphs drawn simultaneously, in MODE (6th line) highlight Simul and press ENTER. Press 2ND QUIT to return to previous screen . Execute graph again.
Hope itr helps.