Question

Simplify 2x(x–5)+3 and find its values for (i) x= 1 (ii) x=-1

Answer 1

2x(x–5)+3 = 2x² -10x + 3 and it value at x= 1 is -5 and value at  x = -1 is 15

Step 1:

Given expression is 2x(x–5)+3

Step 2:

Apply Distributive property a(b + c) = ab + ac

2x² - 10x + 3

Step 3:

Substitute x= 1 and find value at x = 1

2(1)² - 10(1) + 3

= 2 - 10 + 3

= -5

Step 4:

Substitute x= -1 and find value at x = -1

2(-1)² - 10(-1) + 3

= 2 + 10 + 3

= 15

2x(x–5)+3 = 2x² -10x + 3 and it value at x= 1 is -5 and value at  x = -1 is 15