1. Measure and angle in degree
Answer:
20+5x=
Step-by-step explanation:
Answer:
The answer is C
Hope this helps!
Mark me brainliest if I'm right ;)
Answer:
D.
Step-by-step explanation:
All other equations have x or y to the power of one so they are linear. D. has x or y to the power of two, so it's not linear. Quadratics and any variable to the power of 2 and above is not linear (numbers on their own are also always linear, so ignore any powers on them)
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