Question

If (x^2 + ax - 10) ÷ (x + 2) = (x - 5), then a =

Answer 1

A. -7
B. -3
C. 7
D. 3

Answer 2

Then, \(x^2 + ax - 10 = (x - 5)( x+ 2)\)
Do you get it till here?

Answer 3

kinda.....

Answer 4

Yeah. I just multiplied both sides by \(x + 2\).

Answer 5

oh ok

Answer 6

yeah i get it

Answer 7

Great! Can you simplify \((x - 5)(x + 2)\)?

Answer 8

Middle term will be negative because here the factors are -5 and 2..

So "a" will be negative..

Answer 9

@ParthKohli do you mean setting them equal to 0?

Answer 10

So your answer can be either A or B..

You have to check now the sum:

-5 + 2 = ??

Answer 11

Nope.
\(x^2 + a x - 10 = (x + 5)( x - 2)\)
You have to simplify the right hand side by multiplying x + 5 and x - 2.

Answer 12

oh ok so its x^2+3x-10?

Answer 13

@ParthKohli are you there?

Answer 14

Yep :)

Answer 15

Sorry for the late reply, I was eating my dinner.

Answer 16

\( \color{Black}{\Rightarrow (x + 5)(x - 2) = x(x - 2) + 5(x - 2) = x^2 - 2x + 5x - 10 = x^2 + 3 x - 10 }\)

Answer 17

So what is \(a\)?