Answer:
B
Step-by-step explanation:
First distribute the 2x to get:
4x² + 10x
Then distribute the -5 to get:
-10x - 25
Then combine
4x² + 10x - 10x - 25
The 10x's will cancel leaving you:
4x² - 25
A) I would make the positive integer x and then form an equation.
x + 30 = x^2 - 12
x + 42 = x^2
0 = x^2 - x - 42 this can be factorised
(x - 7) ( x + 6) Therefore x = 7 or x = -6
Since the question asks for a positive integer the answer is 7.
B) two positive numbers x and y.
X - y = 3
x^2 + y^2 = 117
Use these simultaneous equations to figure out each number.
Rearrange the first equation
x = y + 3
Then substitute it into the second equation.
(y+3)^2 + y^2 = 117
y^2 + 6y + 9 + y^2 = 117
2y^2 + 6y - 108 = 0
then factorise this.
(2y - 12) (y + 9)
This means that y = 6 or y = -9 but it’s 6 because that’s the only positive number.
Use y to find x
x = y + 3
x = 6 + 3
x = 9
So the answers are x = 9 and y = 6.
Answer:
container y can hold 12.56 more salt
Step-by-step explanation:pls brainlist
40x+8x^2=0 can be solved for x (there are two solutions):
Divide all 3 terms by the greatest common multiple (which is 8x):
40x+8x^2=0
------------- -----
8x 8x
5 + x = 0 produces the root x = - 5.
Setting 8x = 0 and solving for x produces the root x = 0.
Be certain to check these results. substitute x = -5 into 40x+8x^2=0. Is the resulting equation true or false? Next, subs. x=-5 into 40x+8x^2=0. Is the resulting equation true or false?
Answer:
Area=36.66 cm^2
Step-by-step explanation:
First, you need the height.
Use the Pythagorean theorem:
hypotenuse^2=height^2+(1/2 base)^2
It's one-half base because it's an equilateral triangle.
1/2 base =4.6
(9.2)^2-4.6^2=height^2
84.64-21.16=height^2
height^2=63.48
height=7.97
Area=(1/2)(base)(height)
Area=(1/2)(9.2)(7.97)=36.66 cm^2
