OpenStudy (anonymous):

Given the following perfect square trinomial, fill in the missing term. (Do not type the variable in the blank.) 4x^2 + ___x + 49

6 years ago
OpenStudy (campbell_st):

the perfect square is (2x + 7) the middle term is 2*2x*7 = 28x so the blank should be 28

6 years ago

@careless850 Do you remember how to find Discriminant?

6 years ago
$$Discriminant = b^2 - 4ac$$ Since its a perfect square trinmial Discriminant will be 0 (zero) $b^2 - 4ac=0$$b^2 - 4 \times 4 \times 49 =0$$b^2-784=0$Add 784 on both sides $b^2-784 + 784 = 784$$b^2 = 784$Now you take square root on both sides$\sqrt{b^2}-\sqrt{784}$$b=\sqrt{784}$$b=28$