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PLEASE HELP IM STRUGGLING I GOT SICK AND I NEED TO FINISH THIS BY LIKE TOMORROW

B
3y+20
3x+9
E
95⁰
AAFC AEBD
36⁰
49"
7x
na
8x-6
77
D
Use the congruency stateplants to find each valus.
X
BE
GF
ΜΖΑ
DE
MZD
N =
mZK
MZJ
MZH
GK
HL
ATHLAKGJ
3a+21,
H
K
(42)
3a
5a-7
J

PLEASE HELP IM STRUGGLING I GOT SICK AND I NEED TO FINISH THIS BY LIKE TOMORROW B-example-1

1 Answer

2 votes

Answer:

x = 3

y = 5

a = 14

z = 8

AC = ED = 15

BE = FA = 35

CF = DB = 21


m\angle H = m\angle L = m\angle G = m\angle J = 74\°


m\angle F = m\angle B = 36\°


m\angle A = m\angle E = 49\°

Explanation:

First, we have to recognize that dimension of congruent shapes are equal. We are given the congruency statements:


  • \triangle AFC \cong \triangle EBD

  • \triangle THL \cong \triangle KGJ

From these statements, we can equate certain side lengths:


  • AC = ED

  • BE=FA

  • IH = KG

We can also identify through the Isosceles Triangle Theorem that:


  • KG = JK

because
\triangle THL and
\triangle KGJ have congruent base angles and are therefore isosceles triangles.

Hence, we can also declare that:


  • IH = JK

by the transitive property of equality.

Next, we can plug in the labeled values for these side lengths and solve for the variables:


\begin{aligned}AC &= ED\\ 3x+9 &= 8x-6 \\ 9 &= 5x - 6 \\ 15 &= 5x \\ 3 &= x\end{aligned}


\boxed{x=3}


\begin{aligned}AC = ED &= 3x + 9 \\ &= 3(3) + 9\\ &= 9+9 \\ &= 18\end{aligned}


\begin{aligned}CF = DB &= 7x \\ &= 7(3) \\ &= 21\end{aligned}

____________


\begin{aligned}BE &= FA\\ 3y+20 &= 7y \\ 20 &= 4y \\ 5 &= y\end{aligned}


\boxed{y=5}


\begin{aligned}BE = FA &= 7y \\ &=7(5) \\ &= 35\end{aligned}

____________


\begin{aligned}IH &= JK\\ 3a+21&=5a-7 \\ 21&= 2a-7 \\ 28 &= 2a \\ 14 &= a\end{aligned}


\boxed{a=14}

Next, we can solve for z using the fact that CPCTC (Corresponding Parts of Corresponding Triangles are Congruent):


4z = 32


\boxed{z=8}

Finally, we can solve for the isosceles triangles' angle measures using our knowledge that the interior angles of a triangle add to 180°F.

(I will call the isosceles triangles' base angles
b)


\begin{aligned}32 + 2b &= 180\\ 2b&=148\\b&=74\end{aligned}


\boxed{m\angle H = m\angle L = m\angle G = m\angle J = 74\°}

And we can solve for the rest of the angles using CPCTC:


m\angle F = m\angle B = 36\°

Thus,


95 + 36 + m\angle A = 180


m\angle A = 49\° = m\angle E

Further Note

When solving for the angle measures using the Law of Sines, we can see that the given side lengths do not match the angles. For example:


(\sin(m\angle A))/(21) = (\sin(95\°))/(35)


\sin(m\angle A) = (21\sin(95\°))/(35)


m\angle A = \sin^(-1)\!\left((21\sin(96\°))/(35)\right)


m\angle A \approx 36.7\°

User Giorgos Altanis
by
8.6k points