Question

If AB + C = D, find A and C given that when B = 6, D = 30 and when B = 8, D = 36.

Answer 1

equation 1st would be when B=6 and D=30,

6A + C = 30------(1)

equation 2nd would be when B=8 and D=36,

8A + C = 36-------(2)

now substracting equation (1) from (2) we get

 8A + C = 36

-(6A + C) = 30

-----------------------

2A=6

A=3

Put A=3 in equation (1)

6*3 +C = 30

or 18 + C = 30

or C = 30 - 18

C = 12

Answer 2

Equation 1. Equation 2

AB+C=D. AB+C=D

A=? A=?

B=6. B=8

C=? C=?

D=30. D=36

6+6A+C=30+6=8A+C

6A+C+6=8A+C

6+6A=8A

A=2.3

Putting value of A in equation 1

6×2.3+C=30

We get,

C=16.2

When we substitute the value, we get

2.3×6+16.2

Whose answer is 30

Therby the required answer is

A=2.3

B=16.2