Which of the following is a solution made up by x + y=27 and y=2x?
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Answer:
4. x = 9 and y = 18
Step-by-step explanation:
Hello there!
When given such a problem we have to methods to handle this:
On this problem, let's limit ourself to substitution method;
x + y = 27 ..................... eq.1
y = 2x ........................ eq.2
Eq.2 is already manipulated. Substitute it into eq.1
x + y = 27
=> x + 2x = 27
3x = 27
x = 9
Substitute x into eq.2
y = 2 (9)
= 18
In terms of x and y;
(x, y) => (9, 18)
I hope this helps you.
Have a nice time and nice studies.