SOLUTION: 1.If you travel at 120 kilometres per hour how far can you go in 3 3\4 hours 2.The sum of numbers is 2 but their product is -63.what are the numbers 3.One more than -4 is added t

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Question 950398: 1.If you travel at 120 kilometres per hour how far can you go in 3 3\4 hours
2.The sum of numbers is 2 but their product is -63.what are the numbers
3.One more than -4 is added to the product of-6 and less than 10.what is the result?
4.The units digit of a number five more than tens digit.The number is equal to three times the units minus two.determine the number
Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
1.If you travel at 120 kilometres per hour how far can you go in 3 3\4 hours
120 k/hr(3.75 hr)=450 km ANSWER you can travel 450 kilometers.
2.The sum of numbers is 2 but their product is -63.what are the numbers
a and b are the numbers
a+b=2
a=2-b
ab=-63 Substitute for a
(2-b)(b)=-63
-b^2+2b=-63 Add 63 to each side
-b^2+2b+63=0
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ab%5E2%2Bbb%2Bc=0 (in our case -1b%5E2%2B2b%2B63+=+0) has the following solutons:

b%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%282%29%5E2-4%2A-1%2A63=256.

Discriminant d=256 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-2%2B-sqrt%28+256+%29%29%2F2%5Ca.

b%5B1%5D+=+%28-%282%29%2Bsqrt%28+256+%29%29%2F2%5C-1+=+-7
b%5B2%5D+=+%28-%282%29-sqrt%28+256+%29%29%2F2%5C-1+=+9

Quadratic expression -1b%5E2%2B2b%2B63 can be factored:
-1b%5E2%2B2b%2B63+=+-1%28b--7%29%2A%28b-9%29
Again, the answer is: -7, 9. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+-1%2Ax%5E2%2B2%2Ax%2B63+%29

Answers are -7 and 9, one will be a the other b.
ANSWER: The two numbers are -7 and 9.
3.One more than -4 is added to the product of-6 and less than 10.what is the result?
I do not understand this question.
4.The units digit of a number five more than tens digit.The number is equal to three times the units minus two.determine the number
The number must be less than 27 (3 times largest units digit), so tens digit is 1 or 2 1+5+6 and 2+5=7 The number is 16 or 27.
Number=3 times units-2
16=3(6)-2
16 =16 So 16 is one answer.
27=3(7)-2
27=19 FALSE so 27 is not the number
ANSWER The number is 16.
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