#6 plz help me with this question
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Answer:
D. 90
Step-by-step explanation:
All the angles of a triangle will add up to 180 degrees so we will add up everything we are given and set it equal to 180.
(3x) + (x -15 )+ (2x +15) = 180
combine like terms
6x = 180 Keep in mind that the positive 15 and negative 15 cancel
divide by 5
x= 36
But we arent done! we have to go back and plug in everything in to find the greatest angle
3(30) = 90
(30 - 15) = 15
(2(30) + 15) = 45
so the largest number is 90
Answer: Option D. 90°
Step-by-step explanation:
The sum of angles in a triangle = 180°
3x + (x — 15) + (2x + 15) = 180
Clear the bracket
3x + x — 15 + 2x + 15 = 180
6x = 180
Divide both side by 6
x = 180/6 = 30
Substituting the value of, we have:
3x = 3 x 30 = 90
x — 15 = 30 — 15 = 15
2x + 15 = 2(30) + 15 = 60 + 15 = 75
The greatest angle is 90°