If the sin 90° = 1, then which statement is true?
cos 0° = 1, because the cosine and sine are complements
cos 90° = 1, because the cosine and sine are supplements
cos 0° = 0, because the cosine and sine are complements
cos 90° = 0, because the cosine and sine are supplements

cos 0° = 1, because the cosine and sine are complements

step-by-step explanation:

we are given that sin 90° = 1

the sine of any acute angle is equal to the cosine of its complement.

the cosine of any acute angle is equal to the sine of its complement.

we are given

⇒

⇒

since we are given that sin 90° = 1

⇒

thus option a is correct .

cos 0° = 1, because the cosine and sine are complements

step-by-step explanation:

given perimeter: 28cm

length: 9cm

atp,

2(l+w)=p of the reactangle

2(9+x)=28

18+2x=28

2x=28-18

x=10/2

x=5

therefore width is 5 cm

5x + 3y = - 4

step-by-step explanation:

the equation of a line in standard form is

ax + by = c ( a is a positive integer and b, c are integers )

express the line first of all in slope- intercept form

y = mx + c ( m is the slope and c the y-intercept )

to calculate m use the gradient formula

m = ( y₂ - y₁ ) / ( x₂ - x₁ )

with (x₁, y₁ ) = (7, - 3) and (x₂, y₂ ) = (4, - 8)

m = = -

y = - x + c ← is the partial equation

to find c substitute either of the 2 points into the partial equation

using (4, - 8 ), then

- 8 = - + c ⇒ c = -

y = - x - ← in slope-intercept form

multiply all terms by 3 to eliminate the fractions

3y = - 5x - 4 ( add 5x to both sides )

5x + 3y = - 4 ← in standard form