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PLA ANSWER I DONT KNOW THIS

PLA ANSWER I DONT KNOW THIS-example-1
User Juicy
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1 Answer

2 votes

Answer:

x=45

Explanation:

I can give you two solutions

First solution:

In
\triangle FBA we know that


\angle BFA + \angle FAB + \angle ABF=180\\\\90+x+\angle ABF =180\\\\\angle ABF =90-x

same case for
\angle EBC in
\triangle ECB

so we have that


\angle ABC = \angle ABF + \angle FBE +\angle EBC\\\\\angle ABC = 90-x+45+90-x\\\\\angle ABC = 180+45-2x

we leave it like that because it's convenient

Now by properties of parallelograms we know that opposite sides add up to 180


\angle FAB + \angle ABC = 180\\\\x+180+45-2x=180\\\\x+45-2x=0\\\\45-x=0\\\\x=45

so one angle is 45 and the other one is 135

Solution 2

if we look at DEBF we can say that it's a cyclic quadrilateral

because opposite sides add up to 180

in our case


\angle DFB = 180 -\angle BFA = 180-90 = 90\\\\\angle DEB = 90\\\\\Rightarrow \angle DFB + \angle DEB = 180\\\\

so for the other to angles is also true


\angle FDE + \angle EBF = 180\\\\\angle FDE +45 = 180\\\\\angle FDE = 135

so that's the measure of one angle of the parallelogram

the other angle x is


\angle EDF + \angle FAB = 180\\\\135+x=180\\\\x=45

There you go choose yourself

User Maazadeeb
by
5.3k points