12x - 4y = -8
y = 3x + 2
Rewrite the first equation
12x + 8 = 4y
3x + 2 = y
As you see, the first and second equation are actually the same, meaning there's an infinite number of solutions.
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
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Answer:
16
Step-by-step explanation:
2+6=8
8+10=18
18+14=32
6+4=10 10+4=14
an+1=an+(2+4n)
a7=a6+26=72+26=98
a8= a7+30= 98+30=128
a9=a8+34=128+34= 162
a10=a9+38= 162+38=200
a11=a10+42= 242
a12=242+46=288
a13=288+50= 338
a14=338+54= 392
a15=392+58= 450
a16= 450+62=512
Answer:
answer is 1 answer is 4-5 = 1 is 3-6 answer is only 3
Jerry worked 5 hours. Jaun worked 15 hours. Marcia worked 8 hours.
