To multiply terms with exponents, the base of both exponents must be the same. In this case they are so multiply the coefficients and add the exponents:

-2x⁷ x 9x²
(-2 x 9)x^{(7 + 2)}
-18x⁹

Monica scored 87% on the test meaning she earned 87% of the possible points on the test. There were 240 possible points on the test so she earned 240 x 0.87 = 208 points. Each question is worth 4 points so she got \( \frac{208}{4} \) = 52 questions right.

A number in scientific notation has the format 0.000 x 10^exponent. To convert to scientific notation, move the decimal point to the right or the left until the number is a decimal between 1 and 10. The exponent of the 10 is the number of places you moved the decimal point and is positive if you moved the decimal point to the left and negative if you moved it to the right:

0.000933 in scientific notation is 9.33 x 10^-4

The distributive property for multiplication helps in solving expressions like a(b + c). It specifies that the result of multiplying one number by the sum or difference of two numbers can be obtained by multiplying each number individually and then totaling the results: a(b + c) = ab + ac. For example, 4(10-5) = (4 x 10) - (4 x 5) = 40 - 20 = 20.

The amount of flour you need is (2\(\frac{5}{8}\) - \(\frac{3}{8}\)) cups. Rewrite the quantities so they share a common denominator and subtract:

(\( \frac{21}{8} \) - \( \frac{3}{8} \)) cups
\( \frac{18}{8} \) cups
2\(\frac{1}{4}\) cups