Answer:
135
Step-by-step explanation:
(7+3)^2 + (8-1) * 5
Parentheses first
(10)^2 + (7) * 5
Exponents next
100 + 7*5
Multiply
100 + 35
Add
135
1 mm = 0.1 cm
(a) 5 mm
5 × 0.1 = 0.5
Fraction :- 5/0.5
5 ÷ 0.5 =10
Decimal:- 10
(b) 8 mm
8 × 0.1 = 0.8
Fraction:- 8/0.8
8 ÷ 0.8 = 10
Decimal:- 10
Both of your answers are correct. In the first equation, if you were to substitute 3 for x, because you have to do exponents first, you have 3^2, which is 9, and 9*6 =54. If you were to substitute -3 for x again you would have to do the exponents first which would be -3^2 which is 9, and 9*6 = 54.
For the second question, if I substitute 0.75 for t, I get -9 + 18 + 7. This is equal to 16, and therefore the answer would be D. Hope this helps! :D. Let me know if you have questions about my explanation, and feel free to post more questions.
3r-6=-21
3r-6+6=-21+6 (Add 6 to both sides...)
3r=-15
r=-5
3r-6=21
3r-6+6=21+6 (Add 6 to both sides...)
3r=27
r=9
r=-5 or r=9