The question gives you 4 different numbers that could be x, so you have to replace each x in each problem and solve. If the two answers are equivalent, that is your answer. For the first one, 6 times 2 is 12, minus 2 is 10. 5 times 2 is 10, plus 3 is 13. 10 is not equal to 13, so that is not the answer. For 5, 6 times 5 is 30, minus 2 is 28. 5 times 5 is 25, plus 3 is 28, so therefore the answer is x=5
Answer:

Step-by-step explanation:
Graph of x=5 is vertical straight line parallel to y-axis and perpendicular to x-axis. The points on graph have the x-coordinate as 5 and y-coordinate varies.
Similarly, line parallel to x=5 or y-axis passing through point (-6,6), in that all the points have same x-coordinate as -6. So the equation of line will be x=-6
For simplicity of visualization graph of both the equation x=5 and x=-6 are attached.
Let x be the volume (liters) of pure (at 100%) acid needed
Let y be the volume (liters) of the other acid (at 10%) needed
The final solution will be:
a) x+ y = 63 liters, AND their respective concentration in acid: is
100% x & 10% :y that will generate 63 liters at 20%
b) x +0.1 y = 63x 0.2 = 12.6
Let's solve this system of 2 equations:
x + y =63
x + 0.1 y = 12.6
Solving it will give you:
x= 7 liters at 100%
y = 56 liters at 10%
Let x represent the side length of the square end, and let d represent the dimension that is the sum of length and girth. Then the volume V is given by
V = x²(d -4x)
Volume will be maximized when the derivative of V is zero.
dV/dx = 0 = -12x² +2dx
0 = -2x(6x -d)
This has solutions
x = 0, x = d/6
a) The largest possible volume is
(d/6)²(d -4d/6) = 2(d/6)³
= 2(108 in/6)³ = 11,664 in³
b) The dimensions of the package with largest volume are
d/6 = 18 inches square by
d -4d/6 = d/3 = 36 inches long
First find slope
5-10/-1-0= 5
find y-intercept
10=5(0)+B
b=-10
equation: y=5x-10