As y varies directly with x, there is a proportionality constant. As x increases by that certain constant, y also increases. We equate:
y = kx
where k = proportionality constant.
Given the condition, y = 5 when x = 4, then we solve for k:
5 = k(4)
k = 5/4 or 1.25
When y = 8, then
8 = (5/4)(x)
x = 8/(5/4) = (8)(4/5) = 32/5 or 6.4 (ANSWER)
When it says to estimate, I always think of doing it by hand to show work. So set it up like this:
96
<u>x 34</u>
So follow it out multiplying across 4*6 and 4*9 carrying over as needed to get it to look like this:
96
<u>x 34</u>
384
Do the same for the 3 to get this:
96
<u>x 34</u>
384
2880
Add 384+2880=3264
Your final answer is 3,264
5)
Equilateral triangle, all sides are equal
So 2x + 5 = 11
2x = 6
x = 3
Answer is the first one
3; Equilateral theorem
6)
Isosceles triangle has at least two congruent sides.
So 6x = 24
x = 4
Answer x = 4
Converse of the Base Angle Theorem
7)
5x + 7 = 52
5x = 45
x = 9
Answer
x = 9
Base angle theorem
8)
5y - 14 = 3y
2y = 14
y = 7
Answer
7; Equiangular theorem
The equation gives the height of the ball. That is, h is the height of the ball. t is the time. Since we are looking for the time at which the height is 8 (h=8), we need to set the equation equal to 8 and solve for t. We do this as follows:




This is a quadratic equation and as it is set equal to 0 we can solve it using the quadratic formula. That formula is:

You might recall seeing this as "x=..." but since our equation is in terms of t we use "t-=..."
In order to use the formula we need to identify a, b and c.
a = the coefficient (number in front of)

= 16.
b = the coefficient of t = -60
c = the constant (the number that is by itself) = 7
Substituting these into the quadratic formula gives us:



As we have "plus minus" (this is usually written in symbols with a plus sign over a minus sign) we split the equation in two and obtain:

and

So the height is 8 feet at t = 3.63 and t=.12
It should make sense that there are two times. The ball goes up, reaches it's highest height and then comes back down. As such the height will be 8 at some point on the way up and also at some point on the way down.
Answer:
it is adjacent and the answer to 1b is 146