<em>Given - a+b+c = 0</em>
<em>To prove that- </em>
<em>a²/bc + b²/ac + c²/ab = 3</em>
<em>Now we know that</em>
<em>when x+y+z = 0,</em>
<em>then x³+y³+z³ = 3xyz</em>
<em>that means</em>
<em> (x³+y³+z³)/xyz = 3 ---- eq 1)</em>
<em>Lets solve for LHS</em>
<em>LHS = a²/bc + b²/ac + c²/ab</em>
<em>we can write it as LHS = a³/abc + b³/abc + c</em><em>³</em><em>/abc</em>
<em>by multiplying missing denominators,</em>
<em>now take common abc from denominator and you'll get,</em>
<em>LHS = (a³+b³+c³)/abc --- eq (2)</em>
<em>Comparing one and two we can say that</em>
<em>(a³+b³+c³)/abc = 3</em>
<em>Hence proved,</em>
<em>a²/bc + b²/ac + c²/ab = 3</em>
Answer:
cos
(
390
)
−
4
cot
(
−
45
)
sin
(
330
)
Step-by-step explanation:
Answer: Your brother is 15 years old right now.
Step-by-step explanation:
Let be "m" your currently age and "b" your brother's currently age.
Knowing that right now he is three times (this indicates multiplication) as old as you, you can write the following equation:

In five years your age will be:

And your brother's age will be:

Then, if in five years, your brother will be twice as old as you, you can set up the second equation:

Then, the System of equations is:

Apply the Substitution method and substitute the first equation into the second one and solve for "m":

Substitute the value of "m" into the first equation and evaluate in order to find "b":

<span>A. Write and solve an algrebraic equation to find out how many gallons of gas they will use. Explain your steps.
let x = gallons of gas they will use
y = distance traveled
x = y/20
x = 1058/20 = 52.9 gallons of gas
B. Write and solve an algebraic equation to find out how many miles they will travel.
</span>let x = distance traveled
y = gallons of gas used
x = 20y
x = 20(52.9)
x = 1058 miles
Hope this helps. Have a nice day.