q= 6
r= 7
work--
Multiply 1st column by -2:
-30q+8r=-124
5q+8r=86
Subtract 2nd column from the first column:
-35q= -210
Solve for q:
q=6
Subtract q=6 by any of the two equations, so:
-30q+8r=-124
-30*6+8r=-124
Solve for r:
r=7
Answer: 306 cm^2
Step-by-step explanation:
Surface is found by add all the areas of the sides together, including sides, top and bottom. You might need to divide the 3D shape into different shapes in order to find the area of the sides/top/bottoms. Area for rectangle = bxh.
To solve this problem, we are going to use the percent proportion, a/b = p/100, where a is the part of a number b, the whole, and p is the percentage out of 100.
When we fill in our known integers into this equation, we get
21.12 / b = 25.6 / 100
Next, to simplify this equation, we should use cross products (means - extremes products theorem). This means multiplying the numerator of one fraction and the denominator of the other fraction and setting them equal to one another.
21.12(100)=25.6(b)
When we multiply, you get
2112 = 25.6b
Finally, we divide both sides by 25.6, to get our variable b, alone, and without a coefficient.
82.5 = b
Therefore, 25.6% of the number 82.5 is 21.12.
Answer:
Value of x using quadratic formula (x = -4) and (x = -5)
Step-by-step explanation:
Given:
Equation
x² + 9x + 20 = 0
Find:
Value of x using quadratic formula
Computation:
Quadratic formula = [-b±√b²-4ac] / 2a
Given equation;
x² + 9x + 20 = 0
a = 1 , b = 9 , c = 20
By putting value
[-9±√9²-4(1)(20)] / 2(1)
[-9±√81-80] / 2
[-9±√1] / 2
(-9 + 1) / 2 , (-9 - 1) / 2
-8 / 2 , 10 / 2
-4 , - 5
Value of x using quadratic formula (x = -4) and (x = -5)
Answer:
x^2-11x-12
Step-by-step explanation:
I use the box method, which makes a 2x2 box. Then you arrange you numbers based on the equation (show in image)
Then you multiply it out and get the equation
F(x)= x^2+x-12x-12
Simplify your equation and you get
F(x)= x^2-11x-12