Question

help maths qustions help me pls

Answer 1

22.

i. a is equal to 2 and b is equal to 3

ii. 7400

23.

Answer 2

Answer:

22) i) ab = 6

ii) 87² - 13²= 6400

Step-by-step explanation:

22)

i) 22)

i) using formula

${(a + b)}^{2} = {a}^{2} + 2ab + {b}^{2} \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = {a}^{2} + {b}^{2} + 2ab$

5² = 13 + 2ab

25 - 13 = 2ab

2ab = 12

ab = 12/2

ab = 6

ii) using formula,

${a}^{2} - {b}^{2} = (a + b)(a - b)$

${87}^{2} - {13}^{2} = (87 + 13)(87 - 13) \\ = (100)(64) \\ = 6400$