Use algo como cymath. It’s a calculator and it works very well
I know B is true, but i’m unsure for the other choices.
The diagonal of a rectangle = sqrt(w^2 + l^2)
w = width
l = length
In this problem,
The diagonal = 20 in
w = x
l = 2x + 8
Let's plug our numbers into the formula above.
20in = sqrt((x)^2 + (2x + 8)^2)
Let's simplify the inside of the sqrt
20 in = sqrt(5x^2 + 32x + 64)
Now, let's square both sides.
400 = 5x^2 + 32x + 64
Subtract 400 from both sides.
0 = 5x^2 + 32x - 336
Factor
0 = (5x - 28)(x + 12)
Set both terms equal to zero and solve.
x + 12 = 0
Subtract 12 from both sides.
x = -12
5x - 28 = 0
Add 28 to both sides.
5x = 28
Divide both sides by 5
x = 28/5
The width cant be a negative number so now we know that the only real solution is 28/5
Let's plug 28/5 into our length equation.
Length = 2(28/5) + 8 = 56/5 + 8 = 96/5
In conclusion,
Length = 96/5 inches
Width = 28/5
Answer:
x = -5 y = -3
Step-by-step explanation:
-3x + 2y = 9
multiply the 2nd equation by 3 to set it up for elimination
3(x - 3y)= 3(4)
3x-9y = 12
so now combine both to add
-3x + 2y = 9
3x - 9y = 12
Adding both gives you
-7y = 21
divide both by -7 and you get
y = -3
and you substitute y back into equation to get x
x - 3 (-3) = 4 gives you
x + 9 = 4
x = 4 - 9
x = -5
It’s 35 degrees since you do 180-125 to get 35. :)
