First, you much find out how many houses are deliverd in 1 hour.
130/2.5=52
So 52 houses are delivered in 1 hour. Now, divide that by 312.
312/52=6
It would take 6 hours to deliver 312 houses.
The roof will be in the shape of an isosceles triangle with a base length of 30 m and two sides that are 17 m. The two 17 m beams will have the same angle of elevation since they have to might in the middle.
So to find the angle of elevation, we can split the roof in half vertically to create a right triangle. The base will now be 15 m, and the hypotenuse will be 17. Now we can use a trigonometry function to solve for the angle. We know the hypotenuse and the side adjacent to the angle, so we can use cosine.




The answer is 28.1 degrees
Here you have to find which each variable is, for this you start of picking one equation,
x + 2y + 6z = 4
-3x + 2y - 2 = -4
4x + 2z = 16
depending the equation you pick you multiply that by a certain number that will give you the opposite of one of the other equations,
-1(x + 2y + 6z = 4)
= -x -2y - 6z = -4
With this you add or subtract it with the equation that has the same number or variable, or both,
In this case it will be the equation,
-3x + 2y + 6z = 4
You can use this one or the third equation since both have a positive 2y which will cancel with -2y from the new equation,
-x - 2y - 6z = -4
-3x + 2y -z = -4
= -4x -7z = -8
Now you since you just eliminated the variable (y) you now have 2 variables, and the last equation has only 2 variables, meaning now you find the answer to those to equations,
-4x -7z = -8
4x + 2z = 16
= -5z = 8
Now leave the variable by itself,
z = 8/5
Now you found the variable (z), with this just substitute on one of the equations we used to find (z) so you can find (x), after that substitute those answered to on of the original equations so you can find (y)
The discriminant of y=ax^2+bx+c is b^2-4ac
given
9x^2+10x+0
a=9
b=10
c=0
discriminant=10^2-4(9)(0)=100-0=100
the discriminant is 100
Answer:
-5/3
Step-by-step explanation:
Do PEMDAS
8 - 11 = -3
-3 ^ 3 = -27
-(-27) = 27
I-14I = 14
3 x 14 = 42
27 - 42 = -15
2^4 = 16
16 - 7 = 9
-15/9 = -5/3