Let's assume that number as x
The product of 7 and a number =7x
and then increased by 1
so, it will become
=7x+1
now, it is between 15 and 43
so, we can write as

now, we can solve for x
Since, we have to isolate x
step-1:
Subtract all the sides by 1


step-2:
Divide all the sides by 7


so, solution is
.............Answer
Answer:
99.5
Step-by-step explanation:
First quartile is the second largest value in these five
F(x) = -3x² + 6x - 2
First, we make the coefficient of x² equal to 1
f(x) = -3(x² + 2x - 2/3)
Now, we must make the form a² + 2ab + b²
b = 2x/2x
b = 1
f(x) = -3(x² + 2x + 1² - 1² - 2/3)
f(x) = -3(x² + 2x + 1 - 5/3)
f(x) = -3(x + 1)² - 5
The vertex is (-1 , -5)
And this is the maximum point because the coefficient of the squared term is negative.