Please thank you

Write an equation and solve

1. After a car had increased its rate of speed by 21 km/h, it was traveling 60 km/h. What was it original rate of speed?
2. During a charity drive, the senior class raised $85 more than twice the amount raised by the freshman class. The senior class raised $555. How much did the freshman class raise?
3. Nine less than five times a number equals 71. Find the number.
4. Asa has one piece of wire that is 3m+5 inches long and another piece of wire that is 4m-2 inches long. Write and simplify an expression for the total number of inches of wire.

1. 39 km/hr

2. $235

3. 16

4. 7m+3 inches

Step-by-step explanation:

1. Original speed of car: x km

x+21=60

x=39

original speed: 39 km/hr

2. Amount that the freshman class raised: x

2x+85=555

2x=555-85=470

x=235

Amount that the freshman class raised: $235

3. Number: x

5x-9=71

5x=71+9=80

x=16

The number: 16

4.

3m+5+4m-2

= 3m+4m+5-2

=7m+3 inches

d. 8

step-by-step explanation:

the given radical expression is:

we can rewrite this as:

we express as square numbers to get;

the exponents will now cancel out to give.

the correct answer is d

option 3 . (5x + 1) - (-10x + 6)

step-by-step explanation:

option 1 :

(4x + 3) + (-9x + 4)

or 4x+3 -9x + 4

or -5x + 7

option 2

(x - 2) - (6x - 9)

or x-2-6x + 9

or -5x + 7

option 3

(5x+ + 6)

or 5x + 1 + 10x -6

or 15x -5

option 4

-4x+2x+7-3x

-7x + 2x + 7

-5x + 7

hence only option 3 did   not satisfy the given simplify expression.