Estimation is a important skill to know when adding and subtracting decimals because if you estimate you have an idea on what your answer should be close to.
For example 4.68-2.38 could be 5-2 which is 3. 4.68-2.38 equals 2.3. 2.3 is close to 3.
7q² - 28 = 0
+ 28 + 28
7q² = 28
7 7
q² = 4
q = ±4
q = 4 or q = -4
Solution Set: {±4} and {q|q = 4 or q = -4}
Answer:
15 of $3 books and 4 of the $8 books
Step-by-step explanation:
15×3= 45
8 × 4= 34
45+32= 77