We assume the positions of the lines and angles will match the attached figure. The angle addition theorem gives a relation that can be solved for x, then for the value of angle RST.

∠RSU +∠UST = ∠RST

78° + (3x -12)° = (6x +12)° . . . . . substitute given values into the above

54 = 3x . . . . . . . . . . . . . . . . divide by °, subtract 3x+12

108 = 6x . . . . . . . . . . . multiply by 2

120° = (6x +12)° = ∠RST . . . . add 12, show units

The measure of angle RST is 120 degrees.

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<em>Additional comment</em>

Note that we don't actually need to know the value of x (18) in this problem. We only need to know the value of 6x.

7 0

2 years ago

A 6th grade teacher can grade 25 homework assignments in 20 minutes. Is this working at a faster rate or slower rate than gradin

antoniya [11.8K]

This work is faster rate than grading 36 assignments in 30 minutes because :

25 ÷ 20 = 1.25
1.25 hw assignment per minute

36 ÷ 30 = 1.2
1.2 hw assignments per minute

3 0

3 years ago