Friday

October 9, 2015
Posted by **vero** on Sunday, March 11, 2007 at 7:42pm.

Two angles of a triangle are 40 degrees and 62 degrees; what is the third angle's measur?

The angles of a triangle always adds to 180

can you please explained to me clearly beucase I don't understand it

thank you

Angle 1 + angle 2 + angle 3 = 180

Angle 1 = given

angle 2 = given

There is only one unknown in the equation. Solve for angle 3.

If you still don't understand, please explain in detail what you are having trouble understanding.

I do not know how to get the answer for the third angle, if two angles are 40 degrees and third is 62 degrees ; how do I do I do it do I multiplyor how do I get the answer yousee i been out of school for so long that I don't know how to do these math problems, i I have others problems that i haven't donne because I don't understand but thak you for helping me . but please explain these work

angle 1 + angle 2 + angle 3 = 180

angle 1 = 40 from the problem.

angle 2 = 62 from the problem.

angle 3 is not known.

40 + 62 + angle 3 = 180

add 40 + 62 = 102.

102 + angle 3 = 180

angle 3 = 180 - 102 = 78 degrees.

The width of a rectangle is 3 meters less than the length.The perimeter is 14 meters .Find the width.

The second angle of a triangle is twice the first angle. the third angle is 20 degrees mor than the first angle. Find the first angle.

One angle of a triangle is 20 degrees. The second angle's measuremant is four times the third . What is the measure of the third angle?

The sum of two angles in a triangle total 62.5 degrees. What is the other angle's measure?

W = L - 3M

2L + 2W = 14

2L + 2(L-3M) = 14

2L + 2L - 6 = 14

4L - 6 = 14

4L = 14 + 6

4L = 20

L = 20 / 4

L = 5

sub the value of L back into the perimeter fomula to find W.

2L + 2W = 14

2(5) + 2W = 14

10 + 2W = 14

2W = 14 - 10

2W = 4

W = 4 / 2

W = 2

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A + 20 = C

1/2B = A

A+B+C = 180

A+B+(A+20) = 180

2A + B + 20 = 180

2A + B = 180 - 20

2A + B = 160

since we know the value of A sub into formula

2A + B = 160

2(1/2B) + B = 160

B + B = 160

2B = 160

B = 160 / 2

B = 80

A+B+C = 180

A+ 80 + C = 180

A+C = 180 - 80

A + C = 100

from above sub. the value of C into the equation.

A + C = 100

A + (A + 20) = 100

2A + 20 = 100

2A = 100 - 20

2A = 80

A = 80 / 2

A = 40

We found the value of A and B sub. it back into the formula to find C.\

A + B + C = 180

40 + 80 + C = 180

120 + C = 180

C = 180 - 120

C = 60

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A = 20

B = 4C

A + B + C = 180

20 + B + C = 180

B + C = 180 - 20

B + C = 160

from above sub. the value of B into the equation.

B + C = 160

4C + C = 160

5C = 160

C =160 / 5

C= 32 degrees

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180 degrees-62.5 degrees= 117.5 degrees

general review for the high school student.