Question

Given the following diagram, find the missing measure.

m ∠4 = 2x°, m ∠2 = (4/3)x°, m ∠3 = 20°, find x.

A.10
B.20
C.30
D.60

Answer 1

The answer is c, b/c...

20+(4/3)x=2x
-(4/3)x -(4/3)x
20=(2/3)x
20/(2/3)=(2/3)x/(2/3)
30=x

Answer 2

we know that

m ∠4+m ∠1=
`180\°` ------> by supplementary angles

Substitute the value of m ∠4 and find the measure of m ∠1

m ∠1=
`180\°-2x`

Remember that the sum of the internal angles of the triangle is equal to
`180\°`

so

m ∠1+m ∠2+m ∠3=
`180\°`

Substitute the values and solve for x

`180\°-2x\°+(4/3)x\°+20\°=180\°`

`2x\°-(4/3)x\°=20\°`

`(2/3)x\°=20\°`

`x=30\°`

therefore

the answer is the option C

`30\°`