3x+6y=90 what is the y and x intercepts - SoftMath Algebrator - Algebra Homework Solver (689076614429)

Step 1 - replace each x with a y and replace each y with an x
x=6y+24
Step 2 - Solve for y to get the equation in the slope intercept form y=mx+b
Step 3 - get the 24 to the other side by subtracting 24 for both sides
x-24=6y + 24 - 24
Simplify
x - 24 = 6y
Divide by the coefficient in front of the y to get y by itself.
x/6 - 24/6 = y
x/6 -4 = y

Write in the normal format by switching the sides.

y = x/6 - 4

Good luck.

Paul

Parallel lines are lines that go on forever and never cross. In mathematics terms, they have the same slope, but different y-intercepts. For example, y= 3x + 5 and y=3x +7 are parallel lines.

Perpendicular lines are lines that intersect each other at 90 degrees or at right angles. If y=5 and we are looking for a line that intersects it at 90 degrees (or right angles), the line would be x= 4.

Another example would be y = x. The perpendicular line would be y = -x.

To find the perpendicular line, the slope will be the negative reciprocal. For example, y = 3x + 5, the line perpendicular would be y = - 1/3 x + b.

Another way of looking at this is if you take the slopes of the two line and multiply them, you should get -1.

Let me know if you have any questions.

Good luck.

Paul

1) 2x + 5y = 7
2) 3x + 6y = 3

I'm going to use the method of elimination to solve for x and y.
Multiply 1) by 3 and 2) by 2 to allow the x's to be eliminated.

1) 6x + 15y = 21
2) 6x + 12y = 6

Now subtract line 2 from line 1.

0x + 3y = 15
---- ----
3 3 divide both sides by 3 to get y by itself.
y =5.
Substitute into 1) to calculate x.
2x + 5(5) = 7
2x + 25 = 7
2x + 25 -25 = 7 - 25
2x = -18
---- ----- divide both sides by 2 to get x by itself
2 2

x = -9

Check by plugging in answer into the other equation, in this case 2)

3 (-9) + 6(5) = 3
-27 + 30 = 3
3 = 3
We did it correctly and checked to prove that we did it right.

Good luck.

Paul

5x-y=-5 answer x=-1, y= 5 http://www.wolframalpha.com/input/?i=Determine+the+x+and+y+intercept+of+the+graph+for+equation%3A+5x-y%3D-5

-3x+2y=7 answer x = -7/3, y = 7/2 http://www.wolframalpha.com/input/?i=Determine+the+x+and+y+intercept+of+the+graph+for+equation%3A+-3x%2B2y%3D7

Simplify and put it into slope-intercept form:
y=9x-15

From the above the slope is readily seen to be 9 and the y-intercept is -15.

If this is homework be sure to show your work.

y intercept equals -1
x intercept equals -3/4

To get the y-intercept of a line you set x=0. So 3(0)-6y=-21. Solve for y: y=(-21/-6)=7/2.
For the x-intercept, set y=0 in the definition of the function, then you solve for x.
3x-6(0)=-21. or 3x=-21 and x= -21/3=-7

(2x - 3y)(3x + 2y) = 2x*3x + 2x*2y - 3y*3x - 3y*2y
= 6x^2 + 4xy - 9xy - 6y^2
= 6x^2 - 5xy - 6y^2 You multiply each element in the first set of brackets by each element in the second set of brackets and then consolidate like terms and arrange them in sequence of powers, first x and then y. So:
2x by 3x = 6x squared
2x by 2y = 4xy
-3y by 3x = -9xy
-3y by 2y = 6y squared

6x squared -5xy + 6y squared

use the slope-intercept form to graph y=2/3x+4

I am not quite sure what you are asking...

(1) if asking for graphing y= -2/3x+2, then press [diamond] [F1: Y=] type in .2/3x +2, see graph by [diamond][graph]

(2) if asking for graphing y= -2/3x+a, where a=3x, then first archive a=3x in Home screen by [home], type 3x [sto] a, then go back to y= menu, and type -2/3x+a in Y1

(3) if asking for graphing an equation that is dependent on 2 variables at the same time, use x-y-z axis (aka, change mode to graphing 3-D by [mode]graph [5:3D]) then enter desired equation in y= menu using Z function in terms of x and y aka z(x,y)= ...)