Question

The sum of two numbers a and b is 7 and the difference between them is 2. What is the value of a x b ? Give your answer as a mixed number in its simplest form.

Answer 1

Answer:

45/4

Step-by-step explanation:

We can interpret the question to have two equation which can be solve simultaneously

a+b=7------------(1)

a-b=2------------(2)

From eqn(2) make a subject of formula

a=2+b--------(3)

Substitute the (3) into eqn(1)

a+b=7------------(1)

2+b+b=7

2b=7-2

2b=5

b=5/2

From equation (3) substitute value of b to find a

a=2+b--------(3)

a= 2+5/2

a=9/2

Then What is the value of a x b ?

9/2× 5/2

=45/4