Answer:
-2, (-5 is extraneous)
Step-by-step explanation:
assuming √(x+6) -4 =x
√(x+6) = x+4
square both side
x+6 = (x+4)^2
x+6 = x^2+8x+16
x^2+7x+10=0
(x+2)(x+5) = 0
x = -2, -5
put -5 back into org equation and it is not true
√(-5+6) -4 ≠ -5
For the answer to the question above, to solve the average increase between hours 2 and 4, first let as solve the the number of student in each hour
x = 2f(x) = 4x -1f(2) = 4(2) - 1f(2) = 7
x = 3f(x) = 4x -1f(3) = 4(3) - 1f(3) = 11
x = 4f(x) = 4x -1f(4) = 4(4) - 1f(4) = 15
increase in hours 2 to 4increase per hour = 15 - 7 / 4 - 2increase per hour = 4 students per hour
He only used 1/5 of the jar so (1/5*1/4) because he used a fourth of the fifth of the jar the answer is 1/20<span />
43.75 divided by 7 is 6.25, thus your answer is 6.25 hours
I just got free points. Thank you.