Question

Change each standard form equation to slope-intercept form!

Answer 1

Hello! 

Slope-intercept form is this one: $y=a*x+b$ where a is the slope and b the intercept. 

So, for transforming these equations to Slope-Intercept you'll need to rearrange the equations by adding or subtracting the same amounts on both sides of the equation (as a rule of thumb, sums are transformed into subtractions and multiplications into divisions).

1) 3x + y = 12

You should notice that Y and X are on the same side of the equation, so by subtracting 3x on both sides of the equation you'll cancel X on the left side:

$3x+y-3x=12-3x \\ y=12-3x$

To finish, we rearrange this equation to the form y=a*x+b 

$y=-3x+12$

So, the slope is -3 and the intercept is 12

2) 8=y+5x

You should notice that Y and X are on the same side of the equation, so by subtracting 5x on both sides of the equation you'll cancel X on the right side:

$8-5x=y+5x-5x \\ 8-5x=y$

To finish, we rearrange this equation to the form y=a*x+b 

$y=-5x+8$

So, the slope is -5 and the intercept is 8

3) 6x + 3y = -9

You should notice that Y and X are on the same side of the equation, so by subtracting 6x on both sides of the equation you'll cancel X on the left side:

$6x+3y-6x=-9-6x \\ 3y=-9-6x$

Now, you should notice that y has a number that is multiplying it, so you'll need to divide the entire equation by 3 to cancel this number on the left side.

$\frac{3}{3}y= \frac{9}{3}- \frac{6}{3}x \\ y=3-2x$

To finish, we rearrange this equation to the form y=a*x+b 

$y=-2x+3$

So, the slope is -2 and the intercept is 3

4) x - 5y = 55

You should notice that Y and X are on the same side of the equation, so by subtracting x on both sides of the equation you'll cancel X on the left side:

$x-5y-x=-55-x \\ -5y=-55-x$

Now, you should notice that y has a number that is multiplying it, so you'll need to divide the entire equation by -5 to cancel this number on the left side.

$\frac{-5}{-5}y= \frac{55}{-5}- \frac{1}{-5}x \\ y=-11+ \frac{1}{5}x$

To finish, we rearrange this equation to the form y=a*x+b 

$y=\frac{1}{5}x-11$


So, the slope is 1/5 and the intercept is -11

5) -4x-y=-2
You should notice that Y and X are on the same side of the equation, so by adding 4x on both sides of the equation you'll cancel X on the left side:

$-4x-y+4x=-2+4x \\ -y=2+4x$ 

Now, you should notice that y has a number that is multiplying it, so you'll need to divide the entire equation by -1 to cancel this number on the left side.

$\frac{-1}{-1} y= \frac{-2}{-1}+ \frac{4}{-1}x \\ y=2-4x$

To finish, we rearrange this equation to the form y=a*x+b 

$y=-4x+2$

So, the slope is -4 and the intercept is 2

6) -16 = -4x + 2y

You should notice that Y and X are on the same side of the equation, so by adding 4x on both sides of the equation you'll cancel X on the right side:

$-16+4x=-4x+2y+4x \\ -16+4x=2y$

Now, you should notice that y has a number that is multiplying it, so you'll need to divide the entire equation by 2 to cancel this number on the right side.

$\frac{-16}{2}+ \frac{4}{2} x= \frac{2}{2}y \\ -8+2x=y$

To finish, we rearrange this equation to the form y=a*x+b 

$y=2x-8$

So, the slope is 2 and the intercept is -8

I hope that this helps. Have a nice day!