Question

If A = 3 + 5x + 7x2, B = - 4 - 7x + x?
C = 4 + 5x - 8x2, find A + B + C.​

Answer 1

Step-by-step explanation:

Answer

To simplify an algebraic expression that consists of both like and unlike terms, we need to move the like terms together and then add or subtract their coefficients.

Here, the terms are 5x

2

−7x+3,−8x

2

+2x−5 and 7x

2

−x−2. We add these terms as shown below:

(5x

2

−7x+3)+(−8x

2

+2x−5)+(7x

2

−x−2)

=(5x

2

−8x

2

+7x

2

)+(−7x+2x−x)+(3−5−2)

=x

2

(5−8+7)+x(−7+2−1)+(3−5−2)

=4x

2

−6x−4

Hence, (5x

2

−7x+3)+(−8x

2

+2x−5)+(7x

2

−x−2)=4x

2

−6x−4.