Answer:
-2
Step-by-step explanation:
Answer:
<h3>2x+2y = 100</h3>
Step-by-step explanation:
Total number of points in the test = 100points
If the test has x questions worth 2 points apiece, then the total number of points for x questions with 2 points each will be 2 * x i.e 2x........ 1
Also, if y questions worth 4 points apiece then the total number of points for y questions with 4 points each will be 4 * x i.e 4x ....... 2
Total points = eqn 1 + eqn 2
100 = 2x+ 2y
Rearrange
2x+2y = 100
Hence an equation in Standard Form that would model this situation is 2x+2y = 100
Answer:
1. y = 9(x+1/2)^2 -13/4
Step-by-step explanation:
y = 9x^2 + 9x – 1
first isolate the x terms
y = 9(x^2 +x) -1
then add 1/4 inside the brackets to make it a perfect square trinomial (half of the coefficient of the x term squared is how we get 1/4)
since we just added 1/4 we need to subtract what we just added to balance the equation. so 1/4 times 9 is 9/4 ( the number we just added to the equation). then you subtract 9/4 outside of the brackets.
y = 9(x^2 +x +1/4) -1 -9/4
then simplify
y = 9(x+1/2)^2 -13/4
Answer:
a = 9
Step-by-step explanation:
a^2 = 41^2 - 40^2
a^2 = 1681-1600 = 81
a = 9