Consider using the Law of Cosines, because the lengths of three sides are given and the largest angle is the one to be approximated. This angle will be opposite the longest side, that is, opposite the 420-foot side.
420^2 = 250^2 + 300^2 - 2(250)(300)cos A.
Then: 176400 = 62500 + 810000 - 150000cos A.
Solving for cos A, we get:
150000cos A = 176400-62500-810000, or -696100
Then:
-696100
cos A = ------------------- = - 4.64. This is not possible, as the range of the cosine
150000 function is [-1,1].
Using the equation of the line
y -yo = m (x-xo)
We substitute xo,yo and the slope
y -5 = -8(x-1) .....> y = -8x +8 +5 = -8x +13
y = -8x +13
Use the first x then subtract the second x. then the y then the second y. yes it does matter because the numbers you subtract will add up to your answer
Answer:
Let l be the length and w the width of the rectangle.
P as the perimeter and A as the area.
length of a rectangle is four times the width:
w = w
l = 4w
System of equation : 2l + 2w = P
Substitute:
2(4w) + 2w = 45
8w + 2w
10w = 45
w = 45 / 10
w = 4.5
Solve for l:
l = 4w
l = 4(4.5)
l = 18
Area:
A = lw
A = 18(4.5)
A = 81 in²
