Question

como calcular:
8x + 20y = -24
7x + 4y = 6

Answer 1

7x+4y=6
7x=6-4y
x=6-4y/7

8x+20y=-24
8(6-4y/7)+20y=-24
48-32y/7+20y=-24
48-32y+140y/7=-168/7
48-32y+140y=-168
108y=-216
y=-216/108
y=-2

x=6-4y/7
x=6-4(-2)/7
x=6+8/7
x=14/7
x=2