Question

Solve the following system using the substitution method. ----->>>> 3x+y=-3 y=2x+7

coordinate (___,___) ??

Answer 1

(-2,3) ??

Answer 2

we know that y = 2x + 7
so sub 2x + 7 in for y in the other equation

3x + y = -3
3x + 2x + 7 = -3
5x + 7 = -3
5x = -3 - 7
5x = -10
x = -2

now sub -2 in for x in either of the equations
y = 2x + 7
y = 2(-2) + 7
y = -4 + 7
y = 3

check...
3x + y = -3
3(-2) + 3 = -3
-6 + 3 = -3
-3 = -3 (correct)

x = -2 and y = 3 (-2,3)

any questions ?

Answer 3

yes (-2,3)

Answer 4

thank you