Answer:
x = 21
Step-by-step explanation:
4 - 7x +10 = 15 - 6x - 8
-7x + 14 = -6x -7
14 + 7 = -6x + 7x
21 = x or x=21
Answer:

Step-by-step explanation:
From the question we are told that
Charge 
Force 
Generally the equation for electric field strength is mathematically given as


Therefore

Independent variable is 5 means x = 5
solve for f(x) when x = 5
f(5) = -2(5) +1
f(5) = -10 + 1
f(5) = -9
Solution (5,-9)
Answer
B. (5,-9)
Check the picture below.
now, we know that the slanted legs are congruent, since it's an isosceles trapezoid, we also know that the bases are the parallel sides, so, the "altitude" or distance from those bases are the same length, for each of those triangles in the picture.
now, the bases are parallel, that means the altitude segment is perpendicular to the base, the longest side at the bottom, so, we end up with a right-triangle that has a Hypotenuse and a Leg, equal to the other triangle's.
thus, by the HL theorem for right triangles, both of those triangles are congruent, and if the triangles are congruent, all their sides are also, including the ones on the base.