Answer: 23 ft (approximately)
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Explanation:
Draw out a diagram as I've done so below. The unknown side x is opposite the reference angle 68. The hypotenuse (ladder length) is 25.
We'll use the sine rule
sin(angle) = opposite/hypotenuse
sin(68) = x/25
25*sin(68) = x
x = 25*sin(68)
x = 23.1795963641697
x = 23
The ladder reaches approximately 23 feet up on the wall.
I'm rounding to the nearest whole number because the other values given to you were also whole numbers. If your teacher says to round otherwise, then follow those instructions instead.
