Answer:

Step-by-step explanation:
We have been given four choices out of which we need to select the choice which is trinomial.
Trinomial means polynomial having three terms.
A) c2 + c + 6
It has 3 terms.
B) c2 − 16
It has 2 terms.
C) −8c
It has 1 term.
D) c3 + 4c2 − 12c + 7
It has 4 terms.
We see that only choice A) has three terms.
Hence correct choice is 
Answer:

Step-by-step explanation:
Two lines are given to us which are perpendicular to each other and we need to find out the value of a . The given equations are ,
Step 1 : <u>Conver</u><u>t</u><u> </u><u>the </u><u>equations</u><u> in</u><u> </u><u>slope</u><u> intercept</u><u> form</u><u> </u><u>of</u><u> the</u><u> line</u><u> </u><u>.</u>
and ,
Step 2: <u>Find </u><u>the</u><u> </u><u>slope</u><u> of</u><u> the</u><u> </u><u>lines </u><u>:</u><u>-</u>
Now we know that the product of slope of two perpendicular lines is -1. Therefore , from Slope Intercept Form of the line we can say that the slope of first line is ,
And the slope of the second line is ,
Step 3: <u>Multiply</u><u> </u><u>the </u><u>slopes </u><u>:</u><u>-</u><u> </u>
Multiply ,
Multiply both sides by a ,
Divide both sides by -1 ,
<u>Hence </u><u>the</u><u> </u><u>value</u><u> of</u><u> a</u><u> </u><u>is </u><u>9</u><u> </u><u>.</u>