Question

Consider the following system.

y = 4x - 1
y = -3x + 6
Find the solution by using substitution.
HINT: Equal them to each other, solve for x. Then plug in x to one equation to find y.

Answer 1

x=1 y=3

Explanation:

y = 4x - 1

y = -3x + 6

Set the two equations to each other

4x - 1 = -3x + 6

Add 3x to each side

4x +3x - 1 = -3x+3x + 6

7x-1 =6

Add 1 to each side

7x-1+1 = 6+1

7x= 7

Divide each side by 7

7x/7 = 7/7

x=1

Now we can find y

y = 4x-1

y = 4(1)-1

y = 3