using elimination method

Question

-3x+10y=23
5x+2y=55

I need to solve this linear system by using elimination. I don\'t know how to solve it. Can you please help me?

Answer 1

Elimination method:

-3x+10y=23 ------------ (1)

5x+2y=55 --------------- (2)

multiply the equation (2) by 5.

25x+10y=275 ---------- (3)

Eliminate the variable y by subtracting equation 1 from equation 3.

25x + 10y = 275
-3x + 10y = 23 
----------------
28x = 252

divide each side by 28.

28x /28 = 252/28

x = 9

substitute x =9 in equation 2.

5 * 9 + 2y = 55

45 + 2y = 55

subtract 45 from each side.

2y = 55 -45 = 10

divide each side by 2.

y = 10/2 = 5

(x, y) = (9, 5).