Answer:
Step-by-step explanation:
Let's call lifeguarding L and car washing W. In order to write a system, we need to first separate the NUMBER of hours worked from the MONEY earned, because they are very different things.
If she works 10 hours, that is the number of hours worked between both jobs. Therefore, the equation for the NUMBER of hours worked is
L + W = 10.
If she earns $13 an hour lifeguarding, the expression for that is 13L; if she earns $12 an hour car washing, the expression for that is 12W. The MONEY she earned together by doing both those jobs is
13L + 12W = 124
There you go!
Answer:
In mathematics, the determinant is a scalar value that is a function of the entries of a square matrix. It allows characterizing some properties of the matrix and the linear map represented by the matrix.
-- Look at the two numbers.
-- Say to yourself: "Self ! 3.9 is close to 4, and 5.3 is close to 5.
So the product is going to be close to (4 x 5) = 20."
-- Then do the real multiplication.
-- On your paper or your calculator, you see the digits 2 0 6 7 .
-- From your estimate (20), you know that it can't possibly be
2.067 or 206.7 or 2,067. It must be 20.67 .
Answer:
Step-by-step explanation:
Round to 2 inches
A = π(2²) = 4π = 4(3.14) = 12.56 in²
A = π(2.43²) = 18.541386 ≈ 18.54 in²
Answer: B
Step-by-step explanation: You make the values in the parentheses equal to zero.
(X + 3) = 0
X = -3
A is wrong because the root would be 3, not negative 3. C is wrong because 3 isn’t guaranteed to be a root. D is wrong because -3 is a real solution.