Answer:
Kevin needs 96 points on his last test to raise his mean test score to 90 points.
Step-by-step explanation:
we know that
The mean score is the total of all scores divided by the total number of tests.
Let
x_1 ----> the score in the first math test
x_2 ----> the score in the second math test
x_3 ----> the score in the third math test
x_4 ----> the score in the fourth math test
we have
After taking the first 3 tests, his mean test score is 88 points
so

----> equation A
How many points does he need on his last test to raise his mean test score to 90 points?
so

----> equation B
substitute equation A in equation B

solve for x_4


Therefore
Kevin needs 96 points on his last test to raise his mean test score to 90 points.
Answer:
cost of nachos = $3.45
Cost of tacos = $1.5
Step-by-step explanation:
Let
x = cost of nachos
y = cost of tacos
11x + 18y = 64.95 (1)
6x + 15y = 43.20 (2)
Multiply (1) by 6 and (2) by 11 to eliminate x
66x + 108y = 389.70
66x + 165y = 475.20
Subtract to eliminate x
165y - 108y = 475.20 - 389.70
57y = 85.50
y = 85.50/57
y = 1.5
Substitute y = 1.5 to find x
11x + 18y = 64.95 (1)
11x + 18(1.5) = 64.95
11x + 27 = 64.95
11x = 64.95 - 27
11x = 37.95
x = 37.95/11
x = 3.45
cost of nachos = $3.45
Cost of tacos = $1.5
Answer:
2x + 5y = 4.70
Step-by-step explanation:
Rider ordered 2 hot dogs and 5 hush puppies. His total was $4.70. Write an equation in standard form for this relation, using
From the above question, note that
x = cost of a hot dog
y = cost of a hush puppy.
Our Standard Equation is given as
2 × x + 5 × y= $4.70
2x + 5y = 4.70
Answer:
The original equation must have been:

Step-by-step explanation:
A quadratic equation is in the form of :

And it is solved in the form of :
and
Now the given equation is :

We can see that here;
a = 7
b = -5
c = -2
So, the original equation must have been:

Answer:2/8
Step-by-step explanation:
do top and bottom multiply