Answer:
i would say b
Step-by-step explanation:
10.5x = 7.5x + 30
10.5x - 7.5x = 30
3x = 30
x = 30/3
x = 10
10.5(10) = 105
7.5(10) + 30 = 75 + 30 = 105
they need to purchase 10 t-shirts from each company for a total of $105 for each company
Answer:
B. y = -0.58x^2 -0.43x +15.75
Step-by-step explanation:
The data has a shape roughly that of a parabola opening downward. So, you'll be looking for a 2nd-degree equation with a negative coefficient of x^2. There is only one of those, and its y-intercept (15.75) is in about the right place.
The second choice is appropriate.
_____
The other choices are ...
A. a parabola opening upward
C. an exponential function decaying toward zero on the right and tending toward infinity on the left
D. a line with negative slope (This might be a good linear regression model, but the 2nd-degree model is a better fit.)
We have an arithmetic progression:
Nth=an
an=a₁+(n-1)d
a₁ is the first term.
n=number of terms.
d=common difference
10,17,24,31...
a₁=10
d=a₂-a₁=17-10=7
Therefore:
Nth=an
an=a₁+(n-1)d
an=10+(n-1)7
an=10+7n-7
an=7n+3.
Therefore: the formula for the nth is, an=a+(n-1), in this case; an=7n+3,
To check:
a₁=7*1+3=10
a₂=7*2+3=17
a₃=7*3+3=24
a₄=7*4+3=31
a₅=7*5+3=38.......
A quadratic equation has either two different real roots, one real root, or two conjugate complex roots (this is the case when the discriminant is negative, i.e. when you have no real roots).
Two conjugate complex roots have the same real part and opposite imaginary parts. So, the solutions to Amina's equation will be in this form:
For some 
