Study the graph given below. Choose the equation whose graph is given:
(i) y = x (ii) y = 2x

(iii) y = 2x + 1 (iv) x + y = 0

Question

Study the graph given below. Choose the equation whose graph is given: (i) y = x (ii) y = 2x (iii) y = 2x + 1 (iv) x + y = 0

Philoid · Accepted Answer

To find the correct answer, we will try all the options.

There are two points given,

A = (1, 3) and B = ( – 1, – 1)

We will put them in all the equations and check whether they satisfy or not.

(i) y = x

When x = 1 then, y = x

⇒ y = 1 ≠ 3

So it does not satisfy y = x

Therefore, the graph does not satisfy y = x

(ii) y = 2x

When x = 1 then, y = 2x

⇒ y = 2 × 1

⇒ y = 2 ≠ 3

So it does not satisfy y = 2x

Therefore, the graph does not satisfy y = 2x

(iii) y = 2x + 1

When x = 1 then, y = 2x + 1

⇒ y = 2 × 1 + 1

⇒ y = 2 + 1

⇒ y = 3

So it satisfies y = 2x

Now When x = – 1 then, y = 2x + 1

⇒ y = 2 × – 1 + 1

⇒ y = – 2 + 1

⇒ y = – 1

So it also satisfies y = 2x

Therefore, the graph satisfies y = 2x + 1

(iv) x + y = 0

When x = 1 then, y = – x

⇒ y = – 1 ≠ 3

So it does not satisfy x + y = 0

Therefore, the graph does not satisfy x + y = 0

Study the graph given below. Choose the equation whose graph is given:(i) y = x (ii) y = 2x(iii) y = 2x + 1 (iv) x + y = 0