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3 years ago

Please helpp! I will mark Brainliest!

Mathematics

2 answers:

Whitepunk [10]3 years ago

8 0

Answer:

x=7

y=2

Step-by-step explanation:

x-3y=1 ...(1)

3x-5y=11 ...(2)

subtract first from second eq.

3x-5y-(x-3y)=11-1

3x-5y-x+3y=10

2x-2y=10

x-y=5 ...(3)

(3)-(1) gives

2y=4

y=4/2=2

from (3)

x-2=5

x=5+2=7

leva [86]3 years ago

7 0

Do you mind typing the equation it looks incomplete.

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Please help me please it’s this question

Lera25 [3.4K]

Subtract 124 and 18

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2 years ago

#1 Find the slope given the points (3,-20) and (5,8) *

Artyom0805 [142]

Hey there :)

To find the slope with two points we will need to use the equation $\frac{y^2-y^1}{x^2-x^1}$

$x^1$ $x^2$ $y^1$ $y^2$

( 3 , -20 ) ( 5 , 8 )

Here is what the equation should look like when replaced with the numbers (it will be a fraction) :

$\frac{8 - (-20)}{5 - 3}$

We know that two negatives cancel out and make a positive, so the numerator would actually be 8 + 20.

Solve the fraction and we get $\frac{28}{2}$

28 divided by 2 is 14. The slope is 14.

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2 years ago

Given that sin x = cos 2x find the value of x

natali 33 [55]

Answer:

The most straightforward way to obtain the expression for cos(2x) is by using the "cosine of the sum" formula: cos(x + y) = cosx*cosy - sinx*siny. cos(2x) = cos² (x) - (1 - cos²(x)) = 2cos²(x) - 1. = 2cos²(x) - 1.

Step-by-step explanation:

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2 years ago

Whoever checks my work and tell what I did wrong and the right answer will

gulaghasi [49]

Answer:

See below

Step-by-step explanation:

I believe that you only had to do letters F, H, and J. In that case, let's go over each one!

F: For isolating $d_{1}$ , we need to get rid of the 1/2 first. Let's multiply each side by 2:

$2*m = 2*\frac{1}{2}(d_{1}+ d_{2}) \\2m = d_{1}+ d_{2}$

After this, we just subtract $d_{2}$ from each side to get $d_{1}=2m- d_{2}$ . Dark Blue is correct! Let's now plug in those numbers below:

$d_{1}=2(10)- 13 = 20-13=7$

G: Let's isolate the vw^2 on one side by subtracting y from each side:

$vw^{2} +y-y=x-y\\vw^{2}=x-y$

Let's now divide each side by v, then put each side under a square root to get our final answer:

$\frac{vw^2}{v} = \frac{x-y}{v}\\ w^2 = \frac{x-y}{v}\\\sqrt{w^2} = \sqrt{\frac{x-y}{v}} \\w=\sqrt{\frac{x-y}{v}}$

Orange is correct! Again, let's solve the problem underneath:

w= $w=\sqrt{\frac{38-(-7)}{5}} = \sqrt{\frac{38+7}{5}} = \sqrt{\frac{45}{5}}=\sqrt{9}=3$

H: This one has some stuff that we haven't worked with quite yet (like terms), but our approach is the same: isolate c on one side of the equation.

$2a-2a+3c=17a-2a+21\\3c = 15a+21\\\frac{3c}{3} = \frac{15a+21}{3}\\c = \frac{15a}{3}+ \frac{21}{3} \\c = 5a+7$

Purple is correct! Let's solve the problem:

$c = 5(\frac{16}{5})+7 = 16+7 = 23$

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2 years ago

A researcher interested in Springfield citizens' shopping habits surveys a randomly selected group of 200 Walmart shoppers. 76%

luda_lava [24]

Answer and Explanation: The results of the survey would not be accurate to the whole of springfield, as the sample was not a random sample. A random sample is where each person in a given area (Springfield in this case) has an equal chance of being surveyed. In this case, only walmart shoppers were surveyed. Therefor, the results can only apply to shoppers at walmart, not the whole of Springfield.

8 0

3 years ago

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