solve the following systems using the graphing method. y= -2x+10, y= -1/2x+1

Question

I have no clue how to do these using the graphing method. Please use step by step. 

Answer 1

Hi Deanna;

Both equations are set =y...

y= -2x+10

y= (-1/2)x+1

This should make it easy.

-2x+10=(-1/2)x+1

Let's subtract 10 from both sides...

-10-2x+10=(-1/2)x+1-10

-2x=(-1/2)x-9

Let's add (1/2)x to both sides...

(1/2)x-2x=(-1/2)x-9+(1/2)x

(-1 1/2)x=-9

(-3/2)x=-9

Let's multiply both sides by -2/3

(-2/3)(-3/2)x=-9(-2/3)

x=18/3

x=6

 

Let's return to the original equations to find y...

y= -2x+10

y=-2(6)+10

y=-12+10

y=-2

Let's double-check

y= (-1/2)x+1

y=(-1/2)(6)+1

y=-3+1

y=-2

 

The lines intersect at (6,-2)

 

 

 

Answer 2

Do you know how to graph the two equations by hand or with a calculator?

 

If so, then graph them on the same set of axes, and identify the intersections of the two graphs. These points where the two graphs cross are your solutions.