Answer:
92 attendees had activity cards
Step-by-step explanation:
Let x be the number of students with activity cards. Then 130-x is the number without, and the total revenue is ...
7x +10(130 -x) = 1024
7x +1300 -10x = 1024 . . . . eliminate parentheses
-3x = -276 . . . . . . . . . . . . . collect terms; subtract 1300
x = 92 . . . . . . divide by 3
92 students with activity cards attended the dance.
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<em>Comment on the solution</em>
Often, you will see such a problem solved using two equations. For example, they might be ...
Let 'a' represent the number with an activity card; 'w' the number without. Then ...
- a+w = 130 . . . . the total number of students
- 7a +10w = 1024 . . . . the revenue from ticket sales
The problem statement asks for the value of 'a', so you want to eliminate w from these equations. You can do that using substitution. Using the first equation to write an expression for w, you have ...
w = 130-a
and making the substitution into the second equation gives ...
7a +10(130 -a) = 1024
This should look a lot like the equation we used above. There, we skipped the extra variable and went straight to the single equation we needed to solve.
-3•-4=12, and -3+-4=-7.
this will turn into
(x-3)(x-4)
set them up to equal zero
x-3=0, x-4=0
solve
x=3, x=4
(a)
Answer:
y = - 2(x + 4)² + 6
Step-by-step explanation:
The equation of a parabola in vertex form is
y = a(x - h)² + k
where (h, k) are the coordinates of the vertex and a is a multiplier
Here (h, k ) = (- 4, 6 ) , thus
y = a(x - (- 4) )² + 6 , that is
y = a(x + 4)² + 6
To find a substitute (- 2, - 2) into the equation
- 2 = a(- 2 + 4)² + 6 ( subtract 6 from both sides )
- 8 = a(2)² = 4a ( divide both sides by 4 )
- 2 = a , thus
y = - 2(x + 4)² + 6 ← equation in vertex form
Answer:
p=5
Step-by-step explanation:
Please give brainliest
