Answer:
12−3xStep-by-step explanation:
The answer is: ALWAYS TRUE .
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Answer:
129
Step-by-step explanation:
If three lines CD, CE and CF extend from point C, then the following addition postulate is true;
<DCE + <ECF = <DCF
If the space between line C D and C E is 75 degrees, then <DCE = 75
If the space between lines C E and C F is 54, then <ECF = 54.
Substitute the given values into the expression above will give;
<DCF =<DCE + <ECF
<DCF = 75+54
<DCF = 129
Hence the measure of <DCF is 129°
Answer:
Step-by-step explanation:
Angles on a straight line add up to 180 so:
180-110 = 70
As this is an isosceles triangle,
y must be 70.
We know y is 70 and there are 2y and one x. A triangle also adds up to 180.
This means:
2y+x = 180
2(70)+x = 180
140+x = 180
x = 40
x = 40 y = 70
Perimeter is adding up all the dues together
if it’s 30
13+5=18
30-18=12
x is 12