Answer:

Step-by-step explanation:
The function is given.

To find : 
The input for the function f(x) is (a + 1).
Replace x with (a + 1).

Expand brackets.

Simplifying.

Hey I have posted a picture the method I use to solve simultaneous equations is change the sign and follow the new sign.
This involves changing the sign for the second equation and solving it
Expand the brackets .You will have to multiply it.
6x2 +10x-3x-5
Final answer will be
6x2+7x-5
x2 means (x square)
A must be parallel to b.
Proof:
∠3 = <span>∠13 (given)
</span>∠15 = <span>∠13 (vertically opposite angles are equal)
Since </span>∠13 = ∠3 and ∠13 = ∠15, ∠15 = <span>∠3
Then, a must be parallel to b (transverse line d cuts parallel lines producing converse alternate angles that are equal (ie </span>∠15 = <span>∠3))
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