A: x+90=180
B: 2x+90=180
C: x-90=180
D: Not enough info
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Answer:
(B) 2x + 90 = 180 is an equation that could be used to find x.
Step-by-step explanation:
Observing at the triangle, we can see that..
- We are aware of two angel measurements, both of which are 45 degrees.
One triangle is exactly 180 degrees and if you add both 2 angel measurements from the triangles...
45 + 45 = 90 degrees
180 - 90 = 90 degrees
As a result, we know that x = 90. Now we find the equation. Lets look at equation B. ( 2x + 90 = 180 )
Step 1 : 90 should be subtracted from both sides.
2x + 90 − 90 = 180 − 90
2x = 90
Step 2 : Divide both sides by 2.
(When I use the symbol /, it signifies I'm dividing.)
2x/2 = 90/2
x = 45
Step 3: Examine your solution to see whether it is right.
2x + 90 = 180
2(45) + 90 = 180
90 + 90 = 180 ✓
This shows that 2x + 90 = 180 is an equation that could be used to find x.
Hope this helps! :D