Answer:
99
Step-by-step explanation:
1₦ = 100 k
₦9.90 =?
=990k
990/10=99
I know the correct answer but I need you to answer my questions first
Answer:
8. 8.80
9. 90
Step-by-step explanation:
Question 8: Use the Pythagorean formula
DE² = DF²+EF²
EF² = DE² - DF²
= 16.2² - 13.6²
= 77.48
EF = √77.48 = 8.80 (Answer)
Question 9: Use the Cosine Rule
GI² = GH² +HI² - 2·GH·HI·Cos ∠GHI
= 60² + 42² - 2·60·42·Cos 123
= 3600 +1764 - (-2744.98)
= 8108.98
GI = √8108.98 = 90
Using a system of equations, it is found that David is 12 years old.
<h3>What is a system of equations?</h3>
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
The variables are given as follows:
- Variable z: Rebecca's age.
David is three times younger than the dad and twice as old as Rebecca, then:
Rebecca is 30 years younger than the dad, hence:
z = y - 30.
Then, since x = 2z and z = y - 30 and y = 3x, we solve for x to find David's age.
x = 2(y - 30)
x = 2(3x - 30)
x = 6x - 60
5x = 60
x = 60/5
x = 12.
David is 12 years old.
More can be learned about a system of equations at brainly.com/question/24342899
#SPJ1
