If all 3 angles of a Triangle MUST equal 180°, then we know that we use the equation (for this triangle) to find the angle measurements as (180-90)/2 which means we are dividing 90/2 which is 45° for each angle. But these angles are different measures, so we have to guess upon this and say that YOUR ANSWER IS D
No, she did the right way!!!!!
10 x 7 = 70
1 x 7 = 7
9 x 7 = 70 - 7
9 x 7 = 63
I would compute sqrt(1 + 160pi^2) first to get approximately 39.75093337
Add this to 1 and we have 40.75093337
Then divide over 2pi to get a final approximate result of 6.48571248
So x = 6.48571248 is one approximate solution
In short, I computed 
only focusing on the plus for now.
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If you were to compute 
you should get roughly -6.167402596 as your other solution. Each solution can then be plugged into the original equation to check if you get 0 or not. You likely won't land exactly on 0 but you'll get close enough.
Answer:
answer is 5d-10=c
hope that helps in any way
