How much packing material is needed to fill the empty space in the bag

If a man is driving at a rate of 80 km per hour, how many kilometers will he travel in 30 minutes? A. 30 km B. 40 km C. 60 km D.

Nat2105 [25]

Answer:25

Step-by-step explanation:

5 0

3 years ago

Tim must read 2 books from a list of 7 recommended books for his summer reading program. In how many different ways can Tim choo

Marianna [84]

There are 21 ways Tim choose 2 books from the 7 recommended book

Solution:

Given that Tim must read 2 books from a list of 7 recommended books for his summer reading program

To find: different ways can Tim choose 2 books from the 7 recommended books

This is a combination problem

A combination is a selection of all or part of a set of objects, without regard to the order in which objects are selected

The formula for combinations is:

$n C_{r}=\frac{n !}{r !(n-r) !}$

where n represents the number of items, and r represents the number of items being chosen at a time

Here we have to choose 2 books from 7 books

Therefore, n = 7 and r = 2

Substituting values in above formula, we get

$\begin{aligned}&7 C_{2}=\frac{7 !}{2 !(7-2) !}\\\\&7 C_{2}=\frac{7 !}{2 ! \times 5 !}\end{aligned}$

For a number n, the factorial of n can be written as,

$n !=n \times(n-1) \times(n-2) \dots \dots \times 2 \times 1$

Therefore, we get

$7 C_{2}=\frac{7 \times 6 \times 5 \times 4 \times 3 \times 2 \times 1}{2 \times 1 \times 5 \times 4 \times 3 \times 2 \times 1}\\\\7C_2 = 7 \times 3 = 21$

Thus there are 21 ways Tim choose 2 books from the 7 recommended book

7 0

3 years ago

What is the equation of the line that passes through the point (5, 4) and has a slope of 6/5

Sati [7]

Answer:

y=6/5x-2

Step-by-step explanation:

y=mx+C

Y=6/5X+C

4=6+c

c=-2

y=6/5x-2

5 0

3 years ago

Somebody help me with this question please

inysia [295]

$j. \: there \: are \: no \: real \: factors.$

4 0

3 years ago

11. What is the location of the vertex of the parabola defined by f(x) = −3x2 − 18x − 35 and in what direction does the parabola

lbvjy [14]

11. The given parabola has equation: $f(x)=-3x^2-18x-35$

We complete the square to have the function in the vertex form: $f(x)=-3(x^2+6x)-35$

$f(x)=-3(x^2+6x+9)+3*9-35$

$f(x)=-3(x^2+6x+9)+27-35$

$f(x)=-3(x+3)^2-8$

The vertex is (-3,-8), the graph opens down because a=-3<0

Ans: B. Vertex: (−3, −8), opens downward

12. We know the graph of $y=x^2$ is a parabola that opens up and has its minimum point at the origin.

The range of this function is $y\ge 0$

A straight line that has its y-intercept below the x-axis (y=3x-6) will not intersect $y=x^2$ and hence will form a system with no solution.

Ans: D. y equals x squared, y equals 3x minus 6

14. We want to find the zeros of $x^2+21x=5x-63$

$x^2+21x-5x+63=0$

$x^2+16x+63=0$

The factored form is $(x+7)(x+9)=0$

$x=-7\:or\: x=-9$

Ans: C. x = −7, −9

15. The given quadratic expression is $6x^2-17x+10$

We split the middle term to obtain:

$6x^2-12x-5x+10=0$

We factor by grouping to get:

$6x(x-2)-5(x-2)=0$

$(x-2)(6x-5)=0$

Ans: D. 6x − 5

8 0

3 years ago

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