21. D. is the answer. Angle Q is 75 degrees. X=30. The triangle is an isosceles angle so therefore there are 2 angles are congruent to each other, Angle R and Angle Q. All three of the angles should add to 180 degrees.
Answer:
175 ft
Step-by-step explanation:
From the question,
(a) ΔABC and ΔEDC are similar because all the angles in ΔABC is equal to the corresponding angles in ΔEDC.
I.e, ΔABC is equiangular to ΔEDC. (AAA).
(b) From the diagram.
for similar angle, ratio of corresponding sides are equal
100/d = 4x/7x
100/d = 4/7
where d = distance across the river
solve for d
d = (100×7)/4
d = 175 ft
The quadratic formula is ![\frac{-b+-\sqrt[2]{b^2-4ac}}{2a}](https://tex.z-dn.net/?f=%5Cfrac%7B-b%2B-%5Csqrt%5B2%5D%7Bb%5E2-4ac%7D%7D%7B2a%7D)
and in the equation ax^2+bx+c=0
so now all you have to do is substitute the numbers into the quadratic formula
Answer:
3
Step-by-step explanation:
cross multiply