Determine which of the following are perfect square expressions. If so, factorise the expressions. (a) x2 + 4x + 4 (b) x2 + 18x + 36
Answers
Step-by-step explanation:
a)x^2 +4x+4
x^2 +2x+2x+4
x(x+2)+2(x+2)
(x+2)(x+2)
b) x^2 +15x+36
x^2+12x+3x+36
x(x+12)+3(x+12)
(x+3)(x+12)
Make my answer as brainlist please
Answer:
12 or -12
Step-by-step explanation:
Consider the equation
0=x2+4x+4
. We can solve this by factoring as a perfect square trinomial, so
0=(x+2)2→x=−2and_2
. Hence, there will be two identical solutions.
The discriminant of the quadratic equation (
b2−4ac) can be used to determine the number and the type of solutions. Since a quadratic equations roots are in fact its x intercepts, and a perfect square trinomial will have 2 equal, or 1
distinct solution, the vertex lies on the x axis. We can set the discriminant to 0 and solve:
k2−(4×1×36)=0k2−144=0(k+12)(k−12)=0k=±12
So, k can either be
12 or −12
.
Hopefully this helps!