Question

If p+q=5 and 3p+2q=20, then what will be the value of 3p+q?

Answer 1

p = 5-q
3(5-q)+2q = 20
q = 5
p= 0
3p+q = 5 ans

Answer 2

3p+q=?            .......(i)

p+q=5               .....(ii)

3p+2q=20         .....(iii)

multiply 2 in (i) we get

2p+2q=10         ....(iv)

sub (iv) from (iii) we get

p=10

putting p=10 in (ii) we get

10+q=5

q=-5

putting p=10 and q=-5 in (i)

3×10+(-5)=30-5=25    Ans