Step-by-step explanation:
y = 0.8x+ 7.2 ..........(1)
20x + 32y = 48 .........(2)
Substitute (1) in (2)
20x +32*(0.8x+7.2) = 48 expand
20x + 25.6x+230.4 = 48 add
45.6x+230.4 = 48 transpose and simplify
45.6x = 48-230.4 = -182.4
x = -182.4 / 45.6
x = -4
Answer:
x=-4, Y=4
Step-by-step explanation:
20x+32(0.8x+7.2)=48
45.6x =48-230.4
x=-4
substitute x=-4 in y eqn
y=-3.2+7.2
y=4
