20 POINTS PLEASE HELP A 12-foot ladder that is leaning against a wall makes a 75.5 degree
angle ​with the level ground.
​
​Which of the following equations can be used to ​determine the height, y, above the ground, in feet, that the ladder ​touches the wall?
A
cos⁡ 75.5=Y12\cos \ 75.5=\frac{Y}{12}cos 75.5=
12
Y
​

B
cos⁡ 75.5=12Y\cos \ 75.5=\frac{12}{Y}cos 75.5=
Y
12
​

C
sin⁡ 75.5=Y12\sin \ 75.5=\frac{Y}{12}sin 75.5=
12
Y
​

D
sin⁡ 75.5=12Y\sin \ 75.5=\frac{12}{Y}sin 75.5=
Y
12
​

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