If the graph of the equation 20x + 21y = 420 cuts the coordinate axes at P and Q, then what is the measure of the length (in units) of PQ?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 29.
For x-intercept, 20x + 21(0) = 420
⇒ 20x = 420
⇒ x = 21
So, the x-intercept is (21, 0)
For y - intercept, 20(0) + 21y = 420
⇒ 21y = 420
⇒ y = 20
So, the y-intercept is (0, 20).
PQ = √[(21 - 0)2 + (0 - 20)2] = √441 + 400 = √841 = 29 units