A rectangle has sides of length 4a + 5 and 4 + a, with a perimeter of 7. Wrote down an equation that involves a. A) 5a + 18 = 7 B) 5a + 9 = 7 C) 10a + 18 = 14 D) 10a + 18 = 7

The answer to your question is the letter D

Step-by-step explanation:

Data

length = 4a + 5

width = 4 + a

Perimeter = 7

Process

1.- Write down the formula of the perimeter of a rectangle

    Perimeter = 2 length + 2 width

2.- Substitution

    Perimeter = 2(4a + 5) + 2(4 + a)

3.- Expand

    Perimeter = 8a + 10 + 8 + 2a

4.- Simplification

    Perimeter = 10a + 18

5.- Substitute the perimeter

                 7 = 10a + 18

ok

step-by-step explanation:

10.416 m/s

step-by-step explantion:

distance=100m

time= 9.6s

average speed=100/9.6

=10.416 m/s