Question

(i) If a + b = 7 and ab = 10, find the value of (a - b).

Answer 1

Step-by-step explanation:

a-b =3 This is the right answer of your question

Answer 2

a+b =7 and ab=10

we can write,

$(a-b)^{2}$= $(a+b)^{2}$-4ab

Substituting the values given,

$(a-b)^{2}$=$7^{2}$ -40

$(a-b)^{2}$= 49 - 40= 9

Under-rooting both sides we get,

a-b=$\sqrt{9}$=3