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1 year ago

Solve the simultaneous equations 3 x + 2 y = 18 3 x + y = 12

Mathematics

1 answer:

natulia [17]1 year ago

8 0

Answer:

x=2 , y=6

Step-by-step explanation:

3 x + 2 y = 18

3 x + y = 12

(-) (-) (-)

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

y = 6

3x+6=12

=>3x=12-6

=>3x=6

=>x=6/3

=>x=2

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Simplify

melomori [17]

Answer: $4\sqrt{3}$

Step-by-step explanation:

For this exercise it is important to remember the following:

$i=\sqrt{-1} \\\\i^2=-1$

Given the following expression:

$-2i\sqrt{-12}$

You can notice that the radicand (the number inside the square root) is negative. Therefore, in order to simplify the expression, you need to follow these steps:

1. Replace $\sqrt{-1}$ with $i$ and simplify:

$(-2i)(i)\sqrt{12}=-2i^2\sqrt{12}=-2(-1)\sqrt{12}=2\sqrt{12}$

2. Descompose 12 into its prime factors:

$12=2*2*3=2^2*3$

3. Substitute into the expression:

$=2\sqrt{2^2*3}$

4. Since $\sqrt[n]{a^n}=a$ , you can simplify it:

$=(2)(2)\sqrt{3}=4\sqrt{3}$

4 0

2 years ago

Given that f.x 3x-2 over x+1 g[x] x +5 evaluate f[-4] and gf [-2]

Jobisdone [24]

The value of f[ -4 ] and g°f[-2] are $\frac{14}{3}$ and 13 respectively.

<h3>What is the value of f[-4] and g°f[-2]?</h3>

Given the function;

$f(x) = \frac{3x-2}{x+1}$
$g(x)=x+5$
f[ -4 ] = ?
g°f[ -2 ] = ?

For f[ -4 ], we substitute -4 for every variable x in the function.

$f(x) = \frac{3x-2}{x+1}\\\\f(-4) = \frac{3(-4)-2}{(-4)+1}\\\\f(-4) = \frac{-12-2}{-4+1}\\\\f(-4) = \frac{-14}{-3}\\\\f(-4) = \frac{14}{3}$

For g°f[-2]

g°f[-2] is expressed as g(f(-2))

$g(\frac{3x-2}{x+1}) = (\frac{3x-2}{x+1}) + 5\\\\g(\frac{3x-2}{x+1}) = \frac{3x-2}{x+1} + \frac{5(x+1)}{x+1}\\\\g(\frac{3x-2}{x+1}) = \frac{3x-2+5(x+1)}{x+1}\\\\g(\frac{3x-2}{x+1}) = \frac{8x+3}{x+1}\\\\We\ substitute \ in \ [-2] \\\\g(\frac{3x-2}{x+1}) = \frac{8(-2)+3}{(-2)+1}\\\\g(\frac{3x-2}{x+1}) = \frac{-16+3}{-2+1}\\\\g(\frac{3x-2}{x+1}) = \frac{-13}{-1}\\\\g(\frac{3x-2}{x+1}) = 13$