Answer:
25
Step-by-step explanation:
2x+2+5x+3=180 (angles on a straight line)
7x+5=180
7x=180-5
7x=175
x=25 (dividing both sides by 7)
The answer is c because if you do 7x60 you'll get 420 and 830-420=410 and 7x80 you'll get 560 and 970-560 is also 410.
<span>When given 3 triangle sides, to determine if the triangle is acute, right or obtuse:
</span>1) Square all 3 sides.
2) Sum the squares of the 2 shortest sides.
3) Compare this sum to the square of the 3rd side.
if sum > 3rd side² Acute Triangle
if sum = 3rd side² Right Triangle<span>
if sum < 3rd side² Obtuse Triangle
1) 1,296 2,401 3,600
2) Sum = 3,697
3) </span><span>3,697 is greater than 3,600
Therefore, the triangle is acute.
Source:
http://www.1728.org/triantest.htm
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