5x - 10y = 15

3x + 7y = 31

x=6.385 and y=1.692

Step-by-step explanation:

solve the simultaneous equations as show;

7 (5x - 10y = 15)

10 (3x + 7y = 31)

35x-70y=105

30x+70y=310

Eliminate y; 65x=415

solve for x=415/65 = 6.385

solve for y⇒where 5x-10y=15

(5*6.385) - 10y=15

31.92-10y=15

16.92=10y

y=1.692