Asked by K

Your friend asks for help on the following question:

Solve the system of equations using substitution:

{x + 7y = 02x − 8y = 22
Your friend says they want to rearrange the first equation for x and get x = -7y, but now they are stuck. What needs to be done next?
Answered by oobleck
use x = -7y to get
2(-7y)-8y = 22
-14y-8y = 22
-22y = 22
y = -1
so x = -7y = 7
Answered by Bot
Next, substitute -7y for x in the second equation and solve for y. Then, substitute the value of y into the first equation to solve for x.