Answer:
Credit remaining after 21 minutes = $30.4
Step-by-step explanation:
Credit remaining on a phone card is a linear function of the total calling time.
When graphed, let the linear function representing the line is,
y = mx + b
Where 'm' = slope of the line
b = y-intercept
From the graph,
Slope of the line = -0.12
y = -0.12x + b
If this line passes through a point (33, 28.96),
28.96 = -0.12(33) + b
b = 28.96 + 3.96
b = 32.92
Therefore, the linear function is,
f(x) = -0.12x + 32.92
where x = calling time
Credit left in the card after 21 minutes,
f(21) = -0.12(21) + 32.92
= -2.52 + 32.92
= $30.4
Remark
There's a lot you don't know here. Are DE and GF parallel? Is B a right angle? You can't assume that it is. The safest way to proceed is to give x in terms of 58 and B. You might get an answer that gives you something like 32 but I don't think you can say that unless you are told somewhere that ABC is a right angle triangle with the right angle at B.
So what to do.
<BAC = 58o That's because <BAC = <IAK They vertically opposite.
<ABC + <BAC + <ACB = 180o All triangles have 180o
<ACB = 180 - 58 - <ABC Solve for an unknown angle of a triangle.
<ACB = 122 - <ABC
x = <ACB Vertically opposite angles.
x = 122 - <ABC Answer It's 32 if ABC is a right angle.
1/3 of the dimensions means to divide the dimensions by 3. This is to figure out what 1/3 of the dimensions are.
Our length is 6, and our width is 9.
Let's divide our length first.
6/3 = 2.
Our length with 1/3 of it's original dimensions is 2.
Let's divide our width now.
9/3 = 3.
Our width with 1/3 of it's original dimensions is 3.
Our dimensions are 2 by 3.
Your answer is A.) 2 in. by 3 in.
I hope this helps!
31. I'm not positive but give it a shot if it is wrong message me back!