Ermm, Don't you think it's 60?
Cause in my caculatons it's 60
There are different ways to solve a quadratic equation, the main ones that i'm thinking about right now are:
1) factor the equation as a product:
ex: x^2+ 4x + 3 =0
(x+3) (x+1) = 0
x=-3 and x=-1 are the solutions.
To find (x+p) and (x+q) you have to think that (p+q )have to be equal to the number that is multiplied by x, in my example it was 4 (3+1=4), (p times q) have to be equal to the last number of the quadratic equation, the one that is not multiplied by any x, that in my example is 3 (3 x 1= 3)
2) The other way to solve a quadratic function is by using a formula:
given: ax^2 +bx +c=0
x= (-b +/- <span>√(b^2 -</span> 4ac)) / 2a
ex: 3x^2 + 4x -2=0
x= (-4 +/- √16-4(3)(-2)) / 6= (-4 +/- √16+24)/6= (-4 +/- <span>√40) / 6
now there are 2 possibilities: x= (-4+</span><span>√40) /6
and
x= (-4 - </span><span>√40) / 6
I hope the examples were clear enough also if i did't get very nice numbers. Look closely to the sings + and -, they are very important</span>
Answer:
x >_ 1
Step-by-step explanation:
Solving an inequality is a lot like solving an equation. Just pretend the inequality symbol is an equal sign!
(also i wont be using the _ or equal to symbol because I'm too lazy, so you'll get >_ or <_ for those, sorry)
8 + 4x >_ 12
-8 -8
4x >_ 4
/4 /4
x >_ 1
Answer: the cost per unit of gas is $0.38
Step-by-step explanation:
Let x represent the cost per unit of electricity.
Let y represent the cost per unit of gas.
During one month, a homeowner used 600 units of electricity and 100 units of gas for a total cost of $344. It means that
600x + 100y = 344- - - - - - - - - -1
The next month, 400 units of electricity and 250 units of gas were used for a total cost of $299.
It means that
400x + 250y = 299- - - - - - - - - -1
Multiplying equation 1 by 400 and equation 2 by 600, it becomes
240000x + 40000y = 137600
240000x + 150000y = 179400
Subtracting, it becomes
- 110000y = - 41800
y = - 41800/- 110000
y = 0.38
Substituting y = 0.38 into equation 1, it becomes
600x + 100 × 0.38 = 344
600x + 38 = 344
600x = 344 - 38 = 306
x = 306/600
x = 0.51
There are 16 possible outcomes.
Out of all 16 outcomes, there is only one way to get the result T T T T.
Therefore, the probability is 1/16 or
<span>
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<span>
0.0625
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</span>
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