Hi there!
There are many ways to find the measure of an exterior angle of a triangle. I'll explain the easiest method to you. As you can see in the image, a line is drawn extending a side of the triangle. In order to find the measure of the exterior angle, we can subtract the measure of the
adjacent interior angle from 180 (a straight angle). Doing this subtraction will give us the measure of the exterior angle.
Hope this helps!! :)
Answer in fraction form: x = 55/4
Answer in decimal form: x = 13.75
Both forms are equivalent, but they say it in a slightly different way.
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Work Shown:
AC/QY = CD/YW
(x+5)/15 = 5/4
4(x+5) = 15*5
4x+20 = 75
4x = 75-20
4x = 55
x = 55/4
x = 13.75
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Explanations:
- The first step is possible because the polygons are similar. Similar figures have their corresponding sides be in the same proportion or ratio. Note how side AC has the double red angle (at point A) and a single red angle (point C). The side QY has the same idea in the same order. This is why AC corresponds to QY. The ratio AC/QY is the same as CD/YW.
- In the second step, I plugged in the expressions that the diagram shows. This is the substitution property.
- On step 3, I cross multiplied. The general format is A/B = C/D cross multiplies to A*D = B*C.
Hiya. I'm going to rewrite the second equation.
By subtracting 5x by both sides, I'll be able to have y by itself:
-y=-5x+13
I'm going to then divide both sides by -1 to get:
y=5x-13.
Then, I'm going to plug that equation into the first equation
3x+2(5x-13)=39
Factor:
3x+10x-26=39
Combine like terms:
13x=65
Divide both sides by 13 to get x by itself to get x=5
Plug this back into the equation of y=5x-13
y=5(5)-13 to get y=12
Answer:
10
Step-by-step explanation:
130+40+x =180
x=10
option 2 is correct
Answer:
y=42
Step-by-step explanation:
y+48+90=180
y=180-138
y=42