Step-by-step explanation:
is this the question you asked
Trigonometric functions which are related by having the same value at complementary angles are called cofunctions. Cofunctions of complementary angles are equal.
A. csc 20' = csc(90-70)=sec 70
B. cos 87' = cos (90-3)=sin 3'
C. csc 40' = csc(90-50) =sec50'
D. tan 15' = tan(90-75)= cot 75'
Among all the option c is not correct.
Option C is false.
Answer:
The distance between Albany and Buffalo along the I90 is 288.8 mi.
The speed of Fabio is 62 mph.
After 1.5 hours, he is 221 miles from Albany.
Things we can calculate here:
Using the relation:
Distance = time*speed.
We can calculate the number of miles that he moved in that 1.5 hours.
D = 62mph*1.5h = 93mi.
If after 1.5 hours, he was 221 miles Albany, then before that he was 93 miles closer to Albany.
His initial position was:
221 - 93 = 128 miles away from Albany.
Now we also can calculate the time left to arrive at Buffalo.
We know that the distance between Albany and Buffalo is 288.8 mi
And he is 221 mi away from Albany.
Then the distance left to Buffalo is:
288.8mi - 221mi = 67.8mi
And the time left will be:
Distance/speed = time
67.8mi/62mph = 1.1 hours.
He needs to drive for another 1.1 hours to get to Buffalo.
Answer:
Step-by-step explanation:
4). a). If the diagonals of a parallelogram are congruent, then it must be a RECTANGLE.
b). If the diagonals of a parallelogram are perpendicular, then it must be a SQUARE.
c). If the diagonals of a parallelogram bisect the angles of the parallelogram, then it must be a RHOMBUS.
d). If the diagonals of a parallelogram are perpendicular and congruent, then it must be a SQUARE.
e). If a parallelogram has four congruent sides, then it must be a SQUARE.
5). Given quadrilateral SELF is a rhombus.
a). All sides of a rhombus are equal,
Therefore, ES = EL = 25
b). Diagonals of a rhombus bisects the opposite angles,
Therefore, m∠ELS = m∠FLS
3x - 2 = 2x + 7
3x - 2x = 7 + 2
x = 9
c). Diagonals of the rhombus bisect the opposite angles, and adjacent angles are supplementary.
m∠ELF = 2(m∠ELS) = 2(2y - 9)
m∠LES = 2(m∠LEF) = 2(3y + 9)
And 2(2y - 9) + 2(3y + 9) = 180
(2y - 9) + (3y + 9) = 90
5y = 90
y = 18