Answer: 
Step-by-step explanation:
<u>Given information</u>
∡ 1 = 90°
∡ 2 = 50°
∡ 3 = x°
Total Angle = 180° <em>(Triangle angle sum theorem)</em>
<u>Given formula</u>
∡ 1 + ∡ 2 + ∡ 3 = Total Angle
<u>Substitute values into the formula</u>
(90) + (50) + (x) = (180)
<u>Combine like terms</u>
140 + x = 180
<u>Subtract 140 on both sides</u>
140 + x - 140 = 180 - 140

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Answer: the last one I think
no sure sorry
Step-by-step explanation:
Use the equation .8x + x = 252
x is the number, and .8 is the decimal equivalent of 80%.
1.8x = 252
x = 140
The volume of a rectangular pyramid = 1/3 ×Area×height
=1/3×L×W×H
if the dimensions were doubled
therefore,
V=1/3 × (9×2)×(14×2)×(10×2)
=1/3×18×28×20
=3360 cubic centimetres
6/8 because maybe you could try the butterfly strategy and the answer would probably be 6/8