The answer should be .
7j+8
There are 8 more than the product of 7 and j
Answer:
Part A) The triangles ABC and EDC are similar by AAA, because the three internal angles are equal in both triangles
Part B) The width of the river is about
Step-by-step explanation:
we know that
If two triangles are similar, then the ratio of its corresponding sides is equal and its corresponding angles are congruent
Part A) we know that
In this problem , triangles ABC and CDE are similar by AAA, because its corresponding angles are congruent
so
m<DCE=m<ACB -----> by vertical angles
m<EDC=m<ABC -----> is a right angle
m<DEC=m<CAB -----> the sum of the internal angles must be equal to 180 degrees
Part B) we know that
The triangles ABC and EDC are similar -------> see Part A
therefore
substitute the values and solve for AB
69.9 is exactly 3 standard deviations away, which means that 78.9 is +3 (more than 3) standard deviations
So the answer is 78.9
Answer:
cos(2x) = 1 - 2sin²(x)
cos(2x) = 2cos²(x) - 1
1/cos(x) = sec(x)
1) (1-cos(2x))/cos(x) = 2sec(x)sin²(x)
Starting from LHS
(1- (1 - 2sin²(x))/cos(x)
2sin²(x)/cos(x)
2sec(x)sin²(x) = RHS
2) 1/sec²(x) = 1 + cos(2x) - cos²(x)
Starting form RHS
1 + 2cos²(x) - 1 - cos²x
cos²x
(1/sec(x))²
1/sec²(x) = LHS