Diketahui persamaan: 2x+y=3 x-2y=-1 Nilai dari x+y adalah .... a. 0 b. 1 c. 2 d. 3 e. 4

Question

Pertanyaan

Diketahui persamaan: 2x+y=3 x-2y=-1 Nilai dari x+y adalah .... a. 0 b. 1 c. 2 d. 3 e. 4

Tampilkan lebih banyak

Answer 1

This question asks for the value of x + y given the system of linear equations {(2x + y = 3), (x - 2y = -1)}. The strategy for solving this is simple—I will start by simplifying the system of equations and then solving for x and y.

To facilitate the solution process, I follow these steps:
1. Solve one of the equations for either variable.
Here, I'll solve equation (1) for y:

2x + y = 3 -> y = 3 - 2x

2. Substitute this result into the other equation.
Replace y in equation (2),

x - 2(3 - 2x) = -1 -> x -6 + 4x = -1 -> 5x =-1 + 6 -> x = 1.

3. Now, sub the value of x into y = 3 - 2x,
y = 3 - 2 (1) = 1.

The systems of equation thus yields x = 1 and y =1.
This means that the sum of x + y equals (1+1), is equal to 2.

The correct answer should therefore be "c. 2."

Pertanyaan

Diketahui persamaan: 2x+y=3 x-2y=-1 Nilai dari x+y adalah .... a. 0 b. 1 c. 2 d. 3 e. 4

Jawaban

Penjelasan

Pertanyaan Panas lebih