Question

Solve for x and y: 3x + 2y = 11 and 2x + 3y = 4. Also find p if p = 8x + 5y

Answer 1

3x+2y=11 ...(i)

2x+3y =4 ...(ii)

multiplying eq.(i) by 2 and eq(ii) by 3, we get

6x+4y=22 ...(iii)

6x+9y=12 ...(iv)

subtracting eq(iv) from eq.(iii). we get

-5y=10 or y=-2

putting in eq.(iii)

6x+4y=22

6x+4(-2)=22

6x=30 or x=5 and y=-2

p=8x+5y
=(8×5)+(5×-2)
=40-10
​​​​​​p=30