X^2 + 4x -21
= (x +7)(x - 3)
hope that helps
Answer:
idk a or c
Step-by-step explanation:
..........solve it like an equation
Answer: 
Step-by-step explanation:
1. Let's write the following formula for calculate the area of a rectangle:

Where
is the lenght (the longer side) and
is the width (the shorter side).
2. You know that the length is 2.5 times as long as the other side, which indicates a multiplication. Then:

3. So, you must substitute
into the equation for calculate the area of the rectangle and then you must simplify.
4. Then, you obtain the following expression:

N= 0.8
this is the answer to ur problem