Question

Solve the system of linear equations using linear combination.

3a + 6b = 45

2a – 2b = –12

Answer 1

Answer:

let the a and b=x

then,

3x+6x=45

9x=45

x=45/9

x=5

Therefore 3a=3*5=15

6b=6*5=30

Answer 2

Answer:

3(a+2b)=45

A+2b=15

A=15-2b

Putting the value a

2(15-2b) - 2b =-12

30-4b-2b=-12

30-6b=-12

-6b=-12-30

-6b=-42

B=-42/-6

B=7_ans (1)

Putting value of b in A

15-2*7

15-14=1_ans(2)