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PLEASE HELP THIS IS DUE IN 20 MINUTES IM STUCK

PLEASE HELP THIS IS DUE IN 20 MINUTES IM STUCK-example-1

2 Answers

2 votes

Answer:

the answer is c, x=5

Explanation:

now, if we look at the pic, there is already one angle given.

and we know that sum interior angles of a triangle must be 180;

so the sum of the other two angles is: angle 2 +angle 3=180-60.

now, let's pick any number and put it into x.

first, if we put 15 into x: 7(15)+5=120,

so 180-(120+60)=0. and for there is another angle, it is invalid.

if we put 6: 7(6)+5=47,

180-(60+47)=73.

let's look at the third angle.

for x=6, the angle UBI is 120°. and we also know that the sum of angles on a horizontal line is always 180°, so 180-120=60, and for the third angle is NOT 73°, this one is also invalid.

if x=5: 7(5)+5=40, 180-(60+40)=80.

the angle UBI= 100°, 180-100=80°;

for 80°+60°+40° equals 180°, the answer c is correct.

User Csabinho
by
5.0k points
7 votes

Answer:

x=5

Explanation:

Because we know the sum of the interior angles should be 180, we can use this to create an equation to solve for x.

60+(7x+3)+(180-20x)=180

Simplify to find that x = 5

If you're confused about where the 180-20x comes from:

The line it lays on is straight, meaning the angle it creates is 180 degrees.

Thus, 180 - known angle = unknown angle.

User Amir Alagic
by
5.2k points