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3 years ago

How resolve this equation 2x^2-3x-y=-5 -x+y=5

1 answer:

7 0

$-x+y=5\Rightarrow y=x+5$

Substitute $y$ in the other equation:
$2x^{2}-3x-(x+5)=-5$
$\Rightarrow 2x^{2}-3x-x-5=-5$
$\Rightarrow 2x^{2}-4x-5=-5$
$\Rightarrow 2x^{2}-4x=0$
$\Rightarrow 2x(x-2)=0$

So either
$2x=0\Rightarrow x=0\Rightarrow y=0+5=5$
or
$x-2=0\Rightarrow x=2\Rightarrow y=2+5=7$

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I need help with this , please help

PIT_PIT [208]

Start with the 3 then move on

3 0

3 years ago

A man saves 4% of his monthly

Reptile [31]

Answer:

Although the question is not clear, It most likely looks like you were asking for the calculation of the savings for the month after increase.

savings for the month after increase = $1172.4

Step-by-step explanation:

First, let us calculate how much was saved before the increase in savings:

monthly income = $19,540

Percentage saved = 4% of monthly income

= 4/100 × 19,540 = 0.04 × 19,540 = $781.6

Next, we are given the ratio of increase in savings as 3:2

Let the new savings amount be x

3 : 2 = x : 781.6

$\frac{3}{2} = \frac{x}{781.6} \\781.6\ \times 3\ =2x\\2344.8 = 2x\\x =\frac{2344.8}{2} \\x = \$1172.4$

therefore savings for the month after increase = $1172.4

Just incase you were looking for the savings before the increase, the answer is $781.6 (as calculated above)

4 0

3 years ago

Last week, Ray worked 46 hours. He incorrectly calculated he earned $45 of additional pay. What was Ray's error when he miscalcu

astra-53 [7]

Answer: +$45

Step-by-step explanation: if his actual pay for the week was $100 then from the question he incorrectly calculated it as {$100 + $45} = $145 which is $45 above his actual pay.

Error = measured value - actual

value.

= $145 -$100 =$45.

NOTE: since the value he assumed{$145} is greater than his actual pay{$100}, we have to include a positive sign to the error{$45}.

Therefore, Error = +$45.

6 0

3 years ago

Prove that.....cos^2α(cosec^2α-cot^2α)=cos^2α

Dafna1 [17]

Step-by-step explanation:

We must prove that

cos²a(csc²a-cot²a) = cos²a

If we look at both sides, we can see that we have cos²a * something = cos²a. Therefore, if we can get that something to equal 1, we have our proof. In this case, that something is csc²a-cot²a. Using this information, we can work from within the parenthesis and go from there.

We can start by expanding the items in the parenthesis. Taking that csc(x) = 1/sin(x) and cot(a) = cos(x)/sin(x), we can say that

cos²a(csc²a-cot²a) = cos²a(1/sin²a - cos²a/sin²a). Because both items in the parenthesis have a denominator of sin²a, we can subtract cos²a from 1 to get

cos²a(1/sin²a - cos²a/sin²a)= cos²a((1-cos²a)/sin²a))

Next, we know that cos²a+sin²a=1, so 1-cos²a = sin²a. Plugging that in, we get

cos²a((1-cos²a)/sin²a)) = cos²a(sin²a/sin²a)

= cos²a(1)

= cos²a

4 0

2 years ago

What does the transformation (x,y) (x+2,y-5) represent?

just olya [345]

Answer:

A translation of 2 units at right and 5 units down

Step-by-step explanation:

we have

(x,y) -----> (x+2,y-5)

This transformation represent a translation

Remember that

A translation is a type of transformation that moves each point in a figure the same distance in the same direction

That means ----->The translation is 2 units at right and 5 units down

4 0

3 years ago