Answer:
D
Step-by-step explanation:
a perfect square trinomial is

factorized is

so as you can see option A and B can't be, because they have -49y^2 and it has to be plus
so the other options are C and D
in the trinomial a=4 and b=\pm 7
the roots of a^2 and b^2

so it's option d with b=-7

Answer:
Hewo
Step-by-step explanation: Stan BTS
Answer:
10/16 (written as a fraction)
Step-by-step explanation:
Starting point
-(-2x+1)=9-14x
Solve the minus sign
2x-1=9-14x
Swap the Xs and the numbers, changing sign
2x+14x=9+1
Do calculations
16x=10
Result
x=10/16
Answer:a) 54/55
b) 100/110
c) 99/110
Step-by-step explanation:
a)Probability of ordering 4= 9/12×3/11×2/10×1/9 = 54/11880
Probability of 4 good units= 4 × 54/11880
= 216/11880
1/55
1-(1/55) = 54/55
b)Probability of 2 good units= 2 × 54/(11880)
= 108/11880
= 1/110
1- (1/110)= 100/110
c) Probability of exactly 2 units not good= 1 -(100/110) =99/110