Answer:
5.
Step-by-step explanation:
x/y = 0.5
x/10 = 0.5
x = 10*0.5 = 5.
2y = 3x + 21
y = 1.5x + 10.5
plug in, in the second equation
- 4x + (1.5x + 10.5) = 23
-4x + 1.5x + 10.5 = 23
-2.5x + 10.5 = 23
-2.5x = 12.5
x = 12.5/-2.5 = -5
y = 1.5 (-5) + 10.5 = 3
x = -5
y = 3
34.3948
