HELP! The measure of the angles of a triangle are represented by x+30, 4x+30, and 10x-30, the triangle must be:
1) isosceles
2) right
3) obtuse
4) scalene
EXPLAIN PLEASE

Question

HELP! The measure of the angles of a triangle are represented by x+30, 4x+30, and 10x-30, the triangle must be:
1) isosceles
2) right
3) obtuse
4) scalene
EXPLAIN PLEASE

johnweldon1993 · Answer

Alright...so firstly you know that the angles of a triangle add up to 180 correct?

anonymous · Answer

Yes

johnweldon1993 · Answer

So if you just had 3 angles you would add them...like 20 + 70 + 90 = 180 and you would be all set...

same thing here....just add up all these functions and solve for x

$$\large x + 30 + 4x + 30 + 10x - 30 = 180$$

Now combine all your x terms...and combine all your constants and solve for x

what do you get?

anonymous · Answer

x=10

johnweldon1993 · Answer

Very good...now...to figure out your indivdual angles...you plug x = 10 into each of those equations...

x + 30 becomes 10 + 30 = ?
4x + 30 becomes 4(10) + 30 = ?
10x - 30 becomes 10(10) - 30 = ?

anonymous · Answer

40, 70, 70

johnweldon1993 · Answer

Perfect! which is a ____triangle?

anonymous · Answer

so it wouls be isosceles

johnweldon1993 · Answer

Very good :)

anonymous · Answer

Thanks. I have a test on this AND proofs tomorrow.. :(

johnweldon1993 · Answer

Yeah it is kind of confusing when you look at it but when you can step through it like we did here and think about what they ask it's not so bad :)

Good luck on your test tomorrow!!

anonymous · Answer

Thank you, I doubt I will get any of the proofs right