Question

Find two consecutive numbers whose square have the sum 15​

Answer 1

Step-by-step explanation:

• let the two consecutive numbers is x ,x + 1
• $x { }^{2} + (x + 1) {}^{2} = 15 \\ x {}^{2} + x {}^{2} + 1 + 2x = 15 \\ 2x { }^{2} + 2x = 15 - 1 = 14 \\ x { }^{2} + x = 14 \div 2 = 7 \\ x(x + 1) = 7$