Answer:
x=2
Step-by-step explanation:
5x+
= 7
5x+4 =7 (2)
5x+4=14
5x=14-4
5x=10
= 
x=2
<span>Simplifying
4x + 20 = 6x + -10
Reorder the terms:
20 + 4x = 6x + -10
Reorder the terms:
20 + 4x = -10 + 6x
Solving
20 + 4x = -10 + 6x
Move all terms containing x to the left, all other terms to the right.
Add '-6x' to each side of the equation.
20 + 4x + -6x = -10 + 6x + -6x
Combine like terms: 4x + -6x = -2x
20 + -2x = -10 + 6x + -6x
Combine like terms: 6x + -6x = 0
20 + -2x = -10 + 0
20 + -2x = -10
Add '-20' to each side of the equation.
20 + -20 + -2x = -10 + -20
Combine like terms: 20 + -20 = 0
0 + -2x = -10 + -20
-2x = -10 + -20
Combine like terms: -10 + -20 = -30
-2x = -30
Divide each side by '-2'.
x = 15
Simplifying
x = 15</span>
The percentage of walkers who got a ride is 37.5/3=12.5%
The number of that is 0.125*24=3 students.
The correct equation is 8.7 + b = 54.6
because it is given that measure of side a is 8.7cm, in all other equations the values of a is different.
from the first equation we can find the value of b, that is
b = 54.6 - 8.7 = 45.9
so, value of b is 45.9cm