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
The correct answer is 427
We know that:

Substituting known values, we have:

Answer:
The rate at which energy is used is called power.
Step-by-step explanation: