Answer:
Answer C: Becky is 27; John is 31
Step-by-step explanation:
1. John is 4 years older than Becky--27(Becky's age)+ 4=31(John's age)
2. Sum of their ages is 58--27(Becky's age)+31(John's age)=58
So, the correct answer is Answer C.
Answer:
48
Step-by-step explanation:
120*(5/5-3/5)
120*(2/5)
24*2
48
Tim spends 500 minutes at the school.
Step-by-step explanation:
Given,
Time for lunch = 45 minutes
Time for study hall = 45 minutes
Total = 45+45 = 90 minutes
This represents 18% of the total minutes Tim spend at school.
Let,
x be the total minutes Tim spend at school.
18% of x = 90 minutes

Dividing both sides by 0.18

Tim spends 500 minutes at the school.
Keywords: percentage, division
Learn more about division at:
#LearnwithBrainly
Answer:
Step-by-step explanation:
9x⁴ – 2x² – 7 = 0
Let's say that u = x²:
9u² – 2u – 7 = 0
Factor:
(u – 1) (9u + 7) = 0
u = 1, -7/9
Since u = x²:
x² = 1, -7/9
x = ±1, ±i √(7/9)