In Triangle DEF...m
Find the measure of angle F.
I tried this but I got a negative answer. So can someone please help me!?
Thanks in Advance :)
I tried this but I got a negative answer. So can someone please help me!?
Thanks in Advance :)
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Sum of the angles of a triangle = 180°
=> 4x - 10 + 8x - 5 + x^2 + 2x + 10 = 180
=> x^2 + 14x - 185 = 0
=> x = (1/2) [- 14 ± √(196 + 740)]
=> x = (1/2) [- 14 + 30.6] ... [discarding the negative value of x which is not feasible]
=> x = 8.3
=> m∠F = x^2 + 2x + 10 = 95.5°.
=> 4x - 10 + 8x - 5 + x^2 + 2x + 10 = 180
=> x^2 + 14x - 185 = 0
=> x = (1/2) [- 14 ± √(196 + 740)]
=> x = (1/2) [- 14 + 30.6] ... [discarding the negative value of x which is not feasible]
=> x = 8.3
=> m∠F = x^2 + 2x + 10 = 95.5°.
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Sum of the interior angles of a triangle is 180 degree
so
4x - 10 + 8x - 5 + x² + 2x + 10 = 180
x² + 14x - 185 = 0
solve it by using quadratic formula
x = 8.3
Substitute it
angle F is about 95.5 degree
so
4x - 10 + 8x - 5 + x² + 2x + 10 = 180
x² + 14x - 185 = 0
solve it by using quadratic formula
x = 8.3
Substitute it
angle F is about 95.5 degree
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I came up with 95.5 deg.
Add the 3 angles, set the total equal to 180 deg. and use the quadratic equation to solve the resulting equation.
Add the 3 angles, set the total equal to 180 deg. and use the quadratic equation to solve the resulting equation.