The measure of ∠BAF is 54°.
Solution:
DF and CE are intersecting lines.
m∠EAF = 72° and AB bisects ∠CAF.
∠EAF and ∠DAC are vertically opposite angles.
Vertical angle theorem:
<em>If two lines are intersecting, then vertically opposite angles are congruent.</em>
∠DAC ≅ ∠EAF
m∠DAC = 72°
<em>Sum of the adjacent angles in a straight line = 180°</em>
m∠DAE + m∠EAF = 180°
m∠DAE + 72° = 180°
Subtract 72° from both sides.
m∠DAE = 108°
∠CAF and ∠DAE are vertically opposite angles.
⇒ m∠CAF = m∠DAE
⇒ m∠CAF = 108°
AB bisects ∠CAF means ∠CAB = ∠BAF
m∠CAB + m∠BAF = 108°
m∠BAF + m∠BAF = 108°
2 m∠BAF = 108°
Divide by 2 on both sides, we get
m∠BAF = 54°
Hence the measure of ∠BAF is 54°.
Answer:
Company a= 15x+10y+25z+75
Company b=20x+10y+30z+60
Step-by-step explanation:
The complete question is as follows.
The equation a =
can be used to determine the area , <em>a</em>, of a trapezoid with height , h, and base lengths,
and
. Which are equivalent equations?
(a) ![\frac{2a}{h} - b_2 = b_1](https://tex.z-dn.net/?f=%5Cfrac%7B2a%7D%7Bh%7D%20-%20b_2%20%3D%20b_1)
(b) ![\frac{a}{2h} - b_2 = b_1](https://tex.z-dn.net/?f=%5Cfrac%7Ba%7D%7B2h%7D%20-%20b_2%20%3D%20b_1)
(c)
= ![b_1](https://tex.z-dn.net/?f=b_1)
(d) ![\frac{2a}{b_1 + b_2} = h](https://tex.z-dn.net/?f=%5Cfrac%7B2a%7D%7Bb_1%20%2B%20b_2%7D%20%3D%20h)
(e)
= h
Answer: (a)
; (d)
;
Step-by-step explanation: To determine
:
a = ![\frac{1}{2}(b_1 + b_2 )h](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%28b_1%20%2B%20b_2%20%29h)
2a = (
)h
![\frac{2a}{h} = b_1 + b_2](https://tex.z-dn.net/?f=%5Cfrac%7B2a%7D%7Bh%7D%20%3D%20b_1%20%2B%20b_2)
![\frac{2a}{h} - b_2 = b_1](https://tex.z-dn.net/?f=%5Cfrac%7B2a%7D%7Bh%7D%20-%20b_2%20%3D%20b_1)
To determine h:
a = ![\frac{1}{2}(b_1 + b_2 )h](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%28b_1%20%2B%20b_2%20%29h)
2a = ![(b_1 + b_2)h](https://tex.z-dn.net/?f=%28b_1%20%2B%20b_2%29h)
= h
To determine ![b_2](https://tex.z-dn.net/?f=b_2)
a = ![\frac{1}{2}(b_1 + b_2 )h](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%28b_1%20%2B%20b_2%20%29h)
2a = ![(b_1 + b_2)h](https://tex.z-dn.net/?f=%28b_1%20%2B%20b_2%29h)
![\frac{2a}{h} = (b_1 + b_2)](https://tex.z-dn.net/?f=%5Cfrac%7B2a%7D%7Bh%7D%20%3D%20%28b_1%20%2B%20b_2%29)
![\frac{2a}{h} - b_1 = b_2](https://tex.z-dn.net/?f=%5Cfrac%7B2a%7D%7Bh%7D%20-%20b_1%20%3D%20b_2)
Checking the alternatives, you have that
and
= h, so alternatives <u>A</u> and <u>D</u> are correct.
Answer:
Marta need to score at least 94 to receive an average of 90 or higher considering all five tests.
Explanation:
Marks received by Marta in four tests = 86, 84, 97 and 89
Let mark received in fifth test be x
We have average of five test is more than or equal to 90
So we have
![\frac{86+84+97+89+x}{5} \geq 90\\ \\ 86+84+97+89+x\geq 450\\ \\ x\geq 94](https://tex.z-dn.net/?f=%5Cfrac%7B86%2B84%2B97%2B89%2Bx%7D%7B5%7D%20%5Cgeq%2090%5C%5C%20%5C%5C%2086%2B84%2B97%2B89%2Bx%5Cgeq%20450%5C%5C%20%5C%5C%20x%5Cgeq%2094)
So Marta need to score at least 94 to receive an average of 90 or higher considering all five tests.
Answer:
B or A.
Step-by-step explanation: