Posted by **Christopher** on Wednesday, January 5, 2011 at 8:26pm.

in a triangle DEF m<E is three times m<,and m <F is 9 less than m< E

- geometry -
**Henry**, Friday, January 7, 2011 at 7:05pm
D = X deg.

E = 3X,

F = 3X - 9.

X + 3X + (3X - 9) = 180deg.

7X = 180 + 9,

7X = 189,

X = 189 / 7 = 27deg.

D = X = 27deg.

E = 3X = 3*27 = 81deg.

F = 3X - 9 = 3*27 - 9 = 72deg.

## Answer this Question

## Related Questions

- geometry - triangle abc is similar to def, the lengths of the sides of triangle ...
- Geometry - The scale factor of triangle DEF to triangle HJK is 5/2. If EF =15 ...
- Trigonometry/Geometry - In most geometry courses, we learn that there's no such ...
- Geometry - Triangle DEF ~ Triangle HJK, and the scale factor of Triangle DEF to...
- geometry - Triangle ABC is similar to triangle DEF. The sides of ABC are 5,8 and...
- Math (Geometry) - The perimeter of right triangle ABC is equal to the perimeter ...
- math - angle ABC and DEF are supplementary angles. the measure of DEF is 20 ...
- geometry - In similar triangles ABC and DEF, corresponding sides AB and DE equal...
- Math - If triangle ABC is similar to triangle DEF and the perimeter of ABC is 4 ...
- Precalculus - In most geometry courses, we learn that there's no such thing as "...