Properties of equality have nothing to do with it. The associative and commutative properties of multiplication are used (along with the distributive property and the fact of arithmetic: 9 = 10 - 1).
All of these problems make use of the strategy, "look at what you have before you start work."
1. = (4·5)·(-3) = 20·(-3) = -60 . . . . if you know factors of 60, you can do this any way you like. It is convenient to ignore the sign until the final result.
2. = (2.25·4)·23 = 9·23 = 23·10 -23 = 230 -23 = 207 . . . . multiplication by 4 can clear the fraction in 2 1/4, so we choose to do that first. Multiplication by 9 can be done with a subtraction that is often easier than using ×9 facts.
4. = (2·5)·12·(-1) = 10·12·(-1) = (-1)·120 = -120 . . . . multiplying by 10 is about the easiest, so it is convenient to identify the factors of 10 and use them first. Again, it is convenient to ignore the sign until the end.
5. = 0 . . . . when a factor is zero, the product is zero
Answer:
See below
Step-by-step explanation:
Remember that quadratic functions are parabolas when graphed. The solutions are where the parabola crosses the x-axis.
1. The vertex of the parabola in f(x) is (0, 9) which is above the x-axis and the parabola opens up. So the parabola does not cross the x-axis. Therefore the solutions are imaginary.
2. The vertex of the parabola in g(x) is (9, 0) which is on the x-axis and parabola opens up. Therefore, there is a double solution.
3. The vertex of the parabola in h(x) is (-1, -9) which is below the x-axis and the parabola opens up. Therefore, there are two real solutions.
I know this is a long explanation, but that is a way of looking at the problem.
Answer:
430
Step-by-step explanation:
To find the area, use the area for a parallelogram formula:
A = bh, where A is the area, b is the length of the base, and c is the height of the parallelogram.
Next, substitute the values of the base and height:
A = 20in. * 21.5 in.
Finally, simplify the multiplication:
A = 430
Answer: for a the answer is 140° and for b x=25°
Step-by-step explanation:
for a, when you have 2 parallel lines cut by a transversal,the corresponding angles are congruent. and the angle140 is congruent to the corresponding angle as they are vertical angles are congruent.
for b, angle x is congruent to the angle that is supplementary to 155 therefore 180-155=25°
Answer:
8.900101E54
Step-by-step explanation:
