Determine if the following system of equations has no solutions, infinitely many

Two pipes running together can fill a tank in 20 minutes.

Hunter-Best [27]

Answer:

45, 36

Step-by-step explanation:

let x y minutes be the time for pipes to fill the tank, let n be the water needed to fill the tank.

x-y=9

(n/x)*20+(n/y)*20=n

n is removed by dividing the 2nd equation by n

here u get:

(1/x+1/y)*20=1

you sub x=9+y into the above equation

1/y+1/(9+y)=1/20

((9+y)+(y))*20=(9+y)(y)

180+40y=9y+y2

y2-31y-180=0

then use the quadratic formula and u will find y=36 or -5

-5 is rejected because it is negative

x=36+9=45

therefore it is 36 mins and 45 mins

3 0

3 years ago

What is the solution of the equation below?<br> x² - 4= - 5

madam [21]

Answer:

Not possible to work out

Step-by-step explanation:

NO Explanation can be explained as this question cannot be solved

8 0

2 years ago

Write an equation in slope intercept form for the line that has a y intercept of 3 and a slope of -2

charle [14.2K]

Answer:

-2x + 3

Step-by-step explanation:

Trust me, this is the answer.

An explanation:

Slope is rate of change.

if the lady sells 2 cakes in 3 hours, her rate of change, or slope is 2/3.

Y-intercept is where the data enters the graph. It will not always be at the origin of the graph. If on the lady's first day of business, she sold 10 cakes, the Y-intercept is 10. This equation of the lady's business in slope intercept form would be 2/3x + 10. ALWAYS write the slope before x and the y intercept after the + or -- , hope this helps, but -2x + 3 is your answer for sure.

4 0

2 years ago

Is w^2-9w+81 a trinomial square

Yuri [45]

No because it would be
if you knew that
ax^2+bx+c was a trinomial square, then the factored form would be
$( \sqrt{a}x+ \sqrt{c})^{2}$ or $( \sqrt{a}x- \sqrt{c})^{2}$
so
if w^2-9w+81 is perfect square, factored form is either
$( \sqrt{1}x+ \sqrt{81})^{2}$ or $( \sqrt{1}x- \sqrt{81})^{2}$ aka $( x+9)^{2}$ or $( x-9)^{2}$
expand them
(x+9)^2=x^2+18x+81, wron middle term

(x-9)^2=x^2-18x+81 wrong

so it is not

8 0

3 years ago

What is the coefficient of x2y3 in the expansion of (2x + y)5?

Zigmanuir [339]

Option C:

The coefficient of $x^{2} y^{3}$ is 40.

Solution:

Given expression:

$(2 x+y)^{5}$

Using binomial theorem:

$(a+b)^{n}=\sum_{i=0}^{n}\left(\begin{array}{l}n \\i\end{array}\right) a^{(n-i)} b^{i}$

Here $a=2 x, b=y$

Substitute in the binomial formula, we get

$(2x+y)^5=\sum_{i=0}^{5}\left(\begin{array}{l}5 \\i\end{array}\right)(2 x)^{(5-i)} y^{i}$

Now to expand the summation, substitute i = 0, 1, 2, 3, 4 and 5.

$$=\frac{5 !}{0 !(5-0) !}(2 x)^{5} y^{0}+\frac{5 !}{1 !(5-1) !}(2 x)^{4} y^{1}+\frac{5 !}{2 !(5-2) !}(2 x)^{3} y^{2}+\frac{5 !}{3 !(5-3) !}(2 x)^{2} y^{3}$