Question

solve the system of equation, whats the solution.
y=-x+21
y=-2x+30

Answer 1

y=-x+21 move y to the right side and x to the left side
x=21-y then put this in the second equation
y=-2(21-y)+30
y=-42+2y+30
y-2y=-42+30
-y=-12
y=12
x=21-y so x=21-12
x=9

Answer 2

tank you c:

Answer 3

u r welcome

Answer 4

(: