All categories

3 years ago

3x+y=15 5x-4y=8 resolucion de sistema por el metodo de sustitucion

Mathematics

1 answer:

Brrunno [24]3 years ago

8 0

Answer:

x=4

y=3

Step-by-step explanation:

we have the following equations

3x+y=15 equation 1

5x-4y=8 equation 2

using equation 1 we have:

y=15-3x equation 3

using equation 3 in equation 2 we have:

5x-4(15-3x)=8

5x-4*15+4*3x =8

5x-60+12x = 8

17x=68

x=68/17

so we have x=4

finally in equation 3:

y = 15-3(4)

y = 15-12

y = 3

You might be interested in

Graph the following linear function.<br> f(x) = 1/6x+3

Black_prince [1.1K]

Y-axis is 3
x-axis is -18

4 0

2 years ago

7400 dollars is placed in an account with an annual interest

Anastasy [175]

Answer:

Step-by-step explanation:

We have the following equation for compounding annual interest

AV=PV(1+i)ⁿ

We have

19200=7400(1+.06)ⁿ

Solve for n

divide both sides by 7400

2.594=(1.06)ⁿ

then use the following rule for exponents

$x^y=z\\log_xz=y$

which means that

$log_{1.06}2.594=n$

Solve and get

16.362

which rounds to 17

6 0

3 years ago

A long distance runner does a first lap around a track in exactly 50 seconds.As she tires.Each subsequent lap takes 20% longer t

madreJ [45]

Answer:

182 seconds

Step-by-step explanation:

Given:

Time taken for first lap is 50 seconds and each subsequent lap takes 20% longer than previous

Solution:

Time taken for first lap = 50 sec

For second lap

Each subsequent lap takes 20% longer than previous

Previous lap time = 50 sec

second lap = 50 + 20% of 50

second lap $=50+(\frac{20}{100}\times 50)$

second lap $= 50 + 10$

second lap $= 60\ sec$

For third lap

Each subsequent lap takes 20% longer than previous

Previous lap time = 60 sec

Third lap = 60 + 20% of 60

$Third\ lap = 60 + (\frac{20}{100}\times 60)$

$Third\ lap = 60+2\times 6$

$Third\ lap = 60+12$

$Third\ lap = 72\ sec$

Time taken for 3 laps is equal to sum of all three laps time.

$Tiem\ taken\ for\ 3\ lap = 50+60+72$

$Tiem\ taken\ for\ 3\ lap = 182\ sec$

Therefore, it takes 182 seconds (3 min, 2 seconds) to run three laps

6 0

3 years ago

The diagram shows three forces being applied to a crate on a floor. If the crate is to remain stationary, what amount of force m

frozen [14]

Answer:

800 N

Step-by-step explanation:

I don’t know I just submitted it and that was the answer

7 0

3 years ago

Please Help 15 points! Emergency!

Semenov [28]

AA - f(t)=8000(1.5)^t

6 0

3 years ago

Read 2 more answers