Ask this question in the science category xoxo
sin(x) = ⁴/₅
sin⁻¹[sin(x)] = sin⁻¹(⁴/₅)
x ≈ 53.13
cos(90 - x) = cos(90)cos(x) + sin(90)sin(x)
cos(90 - 53.13) = cos(90)cos(53.13) + sin(90)sin(53.13)
cos(36.87) = 0cos(53.13) + sin(53.13)
cos(36.87) = sin(53.13)
cos(36.87) = cos(90 - 53.13)
cos(36.87) = cos(36.87)
Answer is x = -7 and x = -3
<span> x2 + 10x = -21
</span><span> x2 + 10x + 21 = 0
</span>(x +3) (x +7) = 0
(x +3) = 0
and
(x + 7) = 0
so x = - 3 and x = -7
Answer:
The statement is false.
Step-by-step explanation:
A parallelogram is a figure of four sides, such that opposite sides are parallel
A rectangle is a four-sided figure such that all internal angles are 90°
Here, the statement is:
"A rectangle is sometimes a parallelogram but a parallelogram is always a
rectangle."
Here if we found a parallelogram that is not a rectangle, then that is enough to prove that the statement is false.
The counterexample is a rhombus, which is a parallelogram that has two internal angles smaller than 90° and two internal angles larger than 90°, then this parallelogram is not a rectangle, then the statement is false.
The correct statement would be:
"A parallelogram is sometimes a rectangle, but a rectangle is always a parallelogram"
Replace the x in -3^x by 1
Answer is -3^1 = -3