Answer:
x = approx. 1.24 or -7.24
Step-by-step explanation:
It's hard to factor directly so we should use the quadratic formula or complete the square. I'm going to go with completing the square.
x²+6x-9=0
x²+6x=9
x²+6x is the same as x²+2·3·x, in order to make this into the algebraic identity (A+B)²=A²+2AB+B², we must add B², or in this case 3² to both sides. (A is x, B is 3)
x²+6x+9=18
(x+3)²= 18
x+3= ±√18
x= ±4.24 -3 (approximately 4.24)
First solution for x = 4.24-3 = 1.24
Second solution for x = -4.24-3 = -7.24
For this case, what you should do is calculate the surface area of the figure.
We have then:
Triangles:
A1 = (1/2) * (7) * (12)
A1 = 42 in ^ 2
Rectangles:
A2 = (1) * (12.5)
A2 = 12.5 in ^ 2
A3 = (1) * (7)
A3 = 7 in ^ 2
Finally, the total surface area is:
A = 2A1 + 2A2 + A3
Substituting values:
A = 2 (42) + 2 (12.5) + (7)
A = 84 + 25 + 7
A = 116 in ^ 2
Answer:
the amount of cardboard needed to make a box for a single slice of pizza is:
A = 116 in ^ 2
Answer:
161700 ways.
Step-by-step explanation:
The order in which the transistors are chosen is not important. This means that we use the combinations formula to solve this question.
Combinations formula:
is the number of different combinations of x objects from a set of n elements, given by the following formula.

In this question:
3 transistors from a set of 100. So

So 161700 ways.
Answer:
The amount is $155.89
Step-by-step explanation:
To find the cost of the meal, find the tax and tip. You can find each by multiplying the amount of the meal by the percentages.
$119 * 9% = 10.71
$119 * 22% = 26.18
Now we can add all three together.
119 + 10.71 + 26.18 = 155.89