Q2 of 27 Page 90

Find two numbers with sum 4 and product 2.

Let the numbers be x and y.

According to the question

x + y = 4

= y = 4 – x ---- (1)

xy = 2 ---- (2)

by (1) and (2)

x(4–x) = 2

4x – x² = 2

x² – 4x + 2 = 0

We can use the formula

x = 2 + √(2) , 2 – √(2)

Thirty sweets were distributed equally among some kids. Sucking in the sweetness, a budding mathematician said,

“Had we been one less, each would have got one more sweet.”

How many kids were there?

The product of a number and 2 more than that is 168. What are the numbers?

How many terms of the arithmetic sequence 99, 97, 98, … must be added to get 900?

Questions · 27

4. Second Degree Equations

2 3 4 1 1 2 3 4 1 2 3 4 5 6 7 8 1 2 3 4 5 1 2 3 4 5 6