All categories

3 years ago

3х – 8y = 34 7х + 4у = -34 Solve by elimination Y and x Please show steps ):

Mathematics

1 answer:

garri49 [273]3 years ago

4 0

Answer:

The answer would be (-2, -5)

Step-by-step explanation:

3x - 8y= 34

2(7x + 4y = -34)

3x - 8y=34

14x + 8y= -68

----------------------

17x= -34 divided by 17

x = -2

3(-2) -8y= 34

-6 -8y =34 add 6

-8y= 40 divide by -8

y = -5

if you want to check the answer replacing -2 for x and -5 for y

7(-2) + 4(-5)= -34

-14 + (-20) = -34

-34 = -34

I hope this help sorry I'm not good explaining

You might be interested in

Solve the system using elimination.<br> 2x + 18y = -9<br> 4x + 18y = -27

Elan Coil [88]

First, let's cancel out the x by multiplying 2x + 18y = -9 by -2.

-2 ( 2x + 18y = -9) = -4x -36y = 18

Then, we combine the two equations.

-4x + 4x = 0

18y - 36y = -18y

-27 + 18 = -9

Our new equation is -18y = -9.

Now, divide both sides by -18.

-18y / -18 = y

-9/ -18 = 1/2

y = 1/2

We can plug in a value for y since y = 1/2 now.

Let's use 2x + 18y = -9

Plug in y.

2x + 18(1/2) = -9

2x + 9 = -9

Then, subtract 9 from both sides.

2x = -18

Divide by 2.

2x/2 = x

-18/2 = -9

x = -9

Lastly, we can plug in both x and y values to see it works.

2(-9) + 18(1/2) = -9

-18 + 9 = -9

Therefore, the values of x and y does work.

x = -9

y = 1/2

4 0

3 years ago

A pharmaceutical company is conducting a study on whether or not their new vaccine is effective in preventing chicken pox. The r

Fed [463]

Answer:

The answer is "Type 1 error".

Step-by-step explanation:

The error of type I, frequently known as a 'false positive': its error in judgment that perhaps a null hypothesis is simply rejected. This is the mistake of accepting a possible (actual interest hypothesis) hypothesis whenever the results could be attributed to chance since the researchers deny, if valid, the null hypothesis.

5 0

2 years ago

HI pls helppp

Elina [12.6K]

Answer:

A: 1/26

B: 1/50

Step-by-step explanation:

used a calc

8 0

3 years ago

Read 2 more answers

Simplify the expression csc(-x)/1+tan^2x)

Charra [1.4K]

Assuming ya meant $\frac{csc(-x)}{1+tan^2(x)}$

to slimplify, we use a variation of the pythagorean identity and a decomposition into the sin and cos

for the pythaogreaon identity
$cos^2(x)+sin^2(x)=1$
divide both sides by $cos^2(x)$
$1+tan^2(x)=sec^2(x)$ since $\frac{sin(x)}{cos(x)}=tan(x)$
subsitute
$\frac{csc(x)}{sec^2(x)}$

recall that $csc(x)=\frac{1}{cos(x)}$
also that cos(x) is an even function and thus cos(-x)=cos(x)
therfore $csc(-x)=\frac{1}{cos(-x)}=\frac{1}{cos(x)}=csc(x)$
so we get

$\frac{csc(x)}{sec^2(x)}$
decompose them into $\frac{1}{cos(x)}$ and $\frac{1}{sin^2(x)}$ to get $\frac{\frac{1}{cos(x)}}{\frac{1}{sin^2(x)}}$
multiply by $\frac{sin^2(x)}{sin^2(x)}$ to get
$\frac{sin^2(x)}{cos(x)}$
we can furthur simlify to get
$(\frac{sin(x)}{cos(x)})(sin(x))=tan(x)sin(x)$
the expression simplifies to tan(x)sin(x)

5 0

3 years ago

Read 2 more answers

Al's Bakery has a checkbook balance of $1,650. A $700 deposit was made today and will be added to the available balance tomorrow

BigorU [14]

Answer:

20jsbdbdhsnebbjiw jwjwbsnsnenskssmwme jejwinsjeiidd

7 0

2 years ago