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3 years ago

X + 7y = -4 solve for x

Mathematics

2 answers:

zloy xaker [14]3 years ago

7 0

The answer should be <span>X = -4 + -7y</span>

GuDViN [60]3 years ago

4 0

To solve for x
x+7y=-4
x=-4-7y

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PLS HELP IF YOU WANT

Nastasia [14]

Answer:45 * t = 2.5 * (1-t)...the equation will have one solution.

Step-by-step explanation:

For this case, the first thing you should know is:

d: v * t

Where,

d: distance

v: speed

t: time

To go to school by bus we have:

d = 45 * t

To return from school we have:

d = 2.5 * (1-t)

how the distance is the same:45 * t = 2.5 * (1-t)

3 0

2 years ago

Read 2 more answers

3/2 p - 14 = p + 13 <br> Please help

VLD [36.1K]

Answer:

p=54 hope this helps

Step-by-step explanation:

4 0

2 years ago

Hitung jarak di antara titik P(7, 1) dengan titik Q(7, 8)

MaRussiya [10]

Answer:

7 units

Step-by-step explanation:

Distance between 2 points

= $\sqrt{(y1 - y2)^{2} + (x1 - x2) {}^{2} }$

Thus, distance PQ

$=\sqrt{(8 - 1)^{2} + (7 - 7)^{2} } \\ = \sqrt{7^{2} } \\ = 7$

Or you could simply take 8-1= 7 since both points have the same x-coordinate. Thus, PQ is a vertical line and the distance between them is due to the difference in their y-coordinate.

5 0

2 years ago

What number must you add to complete the square?<br> x^2 + 2x = -1

Andru [333]

$\large\begin{array}{l} \textsf{You must add 1 to complete the square.}\\\\ \textsf{There is a very common special product: (square of a sum)}\\\\ \mathsf{(a+b)^2=a^2+2ab+b^2}\\\\\\ \textsf{Take the given equation:}\\\\ \mathsf{x^2+2x=-1\qquad(i)}\\\\\\ \textsf{The first term is a square (x squared)}\\\\ \textsf{The second term is a product of 2, x and 1.} \end{array}$

$\large\begin{array}{l}\\\\\\ \textsf{We need to find a proper value for b, so that if we add it to}\\\textsf{the left side of the equation, we get a perfect square.}\\\\ \textsf{So,}\\\\ \begin{array}{cccccccccc} \mathsf{a^2}&\!\!\!+\!\!\!&\mathsf{2}&\!\!\!\cdot\!\!\!&\mathsf{a}&\!\!\!\cdot\!\!\!&\mathsf{b}&\!\!\!+\!\!\!&\mathsf{b^2}&=\mathsf{(a+b)^2}\\\\ \mathsf{\downarrow}&&&\!\!\!\!\!&\downarrow&\!\!\!\!\!&\downarrow&&\downarrow\\\\ \mathsf{x^2}&\!\!\!+\!\!\!&\mathsf{2}&\!\!\!\cdot\!\!\!&\mathsf{x}&\!\!\!\cdot\!\!\!&\mathsf{1}&\!\!\!+\!\!\!&\mathsf{1^2}&=\mathsf{(x+1)^2} \end{array}\\\\\\ \textsf{Just by comparing the expressions above, we can conclude that}\\\textsf{b must be equal to 1, so we get a perfect square:}\\\\ \mathsf{(x+1)^2=x^2+2x+1} \end{array}$

$\large\begin{array}{l}\\\\\\ \textsf{Back to (i), adding 1 to both sides:}\\\\ \mathsf{x^2+2x+1=-1+1}\\\\ \boxed{\begin{array}{c} \mathsf{(x+1)^2=0} \end{array}} \end{array}$

$\large\begin{array}{l}\\\\\\ \textsf{If you want to solve this equation for x, you will find}\\\\ \mathsf{x+1=0}\\\\ \mathsf{x=-1}\quad\longleftarrow\quad\textsf{(solution)} \end{array}$

If you're having problems understanding the answer, try seeing it through your browser: brainly.com/question/2112248

$\large\begin{array}{l} \textsf{Any doubt? Please, comment below.}\\\\\\ \textsf{Best regards! :-)} \end{array}$

6 0

3 years ago

Read 2 more answers

Traffic along a stretch of road moves at an average speed that varies inversely with the number of cars on it. When there are 15

RSB [31]

Answer:

37.5 miles per hour

Step-by-step explanation:

The traffic along a stretch road moves at an average speed that carried inversely as the number of cars

Average speed= k/number of cars.

When there are 1,500 cars the average speed is 45

The first step is to calculate the constant k

45= k/1500

k = 1,500 × 45

k= 67,500

Therefore the average speed when there are 1,800 cars can be calculated as follows

Average speed= 67,500/1,800

= 37.5 miles per hour

Hence the average speed is 37.5 moles per hour

7 0

3 years ago