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3 years ago

4x²-y²=171 and 2x-y=9, value of 2x+y

1 answer:

8 0

So you will need to solve for x and y before evaluating 2x+y....

2x-y=9, y=2x-9 now this will make 4x^2-y^2=171 become:

4x^2-(2x-9)^2=171

4x^2-(4x^2-36x+81)=171

36x-81=171

36x=252

x=7, now we can use 2x-y=9 to solve for y...

2(7)-y=9

14-y=9

-y=-5

y=5

now we know that x=7 and y=5, 2x+y becomes:

2(7)+5

14+5

19

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Solving Exponential and Logarithmic Equations In Exercise, solve for x.<br> 500(1.075)120x = 100.000

Volgvan

Answer:

The solution is:

$x = 0.61$

Step-by-step explanation:

The first step to solve this equation is placing everything with the exponential to one side of the equality, and everything without the exponential to the other side. So

$500(1.075)^{120x} = 100000$

$(1.075)^{120x} = \frac{100000}{500}$

$(1.075)^{120x} = 200$

To find x, we have to apply log to both sides of the equality.

We also have that:

$\log{a^{x}} = x\log{a}$

$\log{(1.075)^{120x}} = \log{200}$

$120x\log{1.075} = 2.30$

$120x*0.03 = 2.30$

$3.77x = 2.30$

$x = \frac{2.30}{3.77}$

$x = 0.61$

4 0

3 years ago

A 4-kilogram ham costs $16/kg. Find the cost per pound.

dem82 [27]

1kg is 2.20462 pounds
So 4kgs are 8.81849
Divided by $16 would equal 0.551155625
Therefore Each pound will cost 0.551155625

4 0

3 years ago

which is the solutions to the system of equations shown { 3x - y = 6 and here is the other equation{ x - 2y = -18

Vinvika [58]

Answer:

(6, 12)

Step-by-step explanation:

{ 3x - y = 6

{ x - 2y = -18

by using elimination:

6x -2y=12

x - 2y= -18

________-

5x = 30

x = 6

y = 18-6 = 12

the solutions = {(6, 12)}

3 0

2 years ago

Need help asap pls pls pls

Sliva [168]

Answer:

bqidhiwodxh

Step-by-step explanation:

627e29302990331 e7894094902

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6 0

2 years ago

HELP PLEASE I KEEP ASKING AND NO ONE ACTUALLY HELPS

coldgirl [10]

Answer: X = 44.4 degrees

Step-by-step explanation: The figure given is a right angled triangle with two sides given as well as one angle unknown.

Angle X, which is the unknown, is the reference angle in this question. So we have an opposite which is the side facing the reference angle (line 7 units) and we have an hypotenuse which is the side facing the right angle (line 10). Having an opposite and an hypotenuse, we can use the trigonometric ratio of sine.

SinX = opposite/hypotenuse

SinX = 7/10

SinX = 0.7000

Looking up a table of values or checking the calculator, 0.7000 under sine of angles gives 44.4270

Therefore angle X is approximately 44.4 degrees (approximated to the nearest tenth)

3 0

3 years ago