Advertisements
Advertisements
Question
Let y varies directly as x. If y = 12 when x = 4, then write a linear equation. What is the value of y when x = 5?
Advertisements
Solution
Given that, y varies directly as x.
i.e., y ∞ x ⇒ y = kx [where, k = arbitrary constant] ...(i)
Given, y = 12 and x = 4
12 = 4k
⇒ `k = 12/4` ...[From equation (i)]
∴ k = 3
On putting the value of k in equation (i), we get
y = 3x ...(ii)
When x = 5, then from equation (ii), we get
y = 3 × 5 ⇒ y = 15
Hence, the value of y is 15.
APPEARS IN
RELATED QUESTIONS
Give the geometric representations of y = 3 as an equation in one variable.
Give the geometric representations of 2x + 9 = 0 as an equation in one variable.
Draw the graph of the equation 2x + 3y = 12. From the graph, find the coordinates of the
point: (i) whose y-coordinates is 3. (ii) whose x-coordinate is −3.
Give the geometric representation of the following equation
(a) on the number line (b) on the Cartesian plane : 3x – 5 = 0
Solve the equation 3x + 2 = x − 8, and represent the solution on the
Cartesian plane .
Write the equation of the line that is parallel to y-axis and passing through the point (4, 0) .
Write whether the graph of the equation given below is parallel to the X-axis or parallel to the Y-axis.
x + 6 = 0
If 'a' is a real number, what is the distance between the Y-axis and the line x = a?
Any point on the x-axis is of the form ______.
The point of the form (a, a) always lies ______.
