Question

considerando x = 10 - 3y , determine o valor de y na equação 7x - 2y =18

Answer 1

7×(10-3y) -2y= 18
70 - 21y - 2y = 18
70-18= 21y+2y
52=23y
y= 52÷23
y= 2,260

Answer 2

7.(10-3y)-2y=18
70-21y-2y=18
70-23y=18
23y=18-70
23y=52
y=52÷23
y=2,260