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4 years ago

Help me please it’s practice

Mathematics

1 answer:

Burka [1]4 years ago

7 0

-3x+80>20
You then move the 20 to right hand side
-3x>20-80
So 20-80 = -60
-3x>-60
You then divide them

= x < 20

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Kevin caught some fish. Of them 4/9 were herring, and 2/9 salmon. What was the total amount of fish, amount of herring and amoun

julia-pushkina [17]

There were 3 different fish caught, Salmon, Herring and Flounder.

4/9 were Herring, 2/9 were Salmon, 4/9 +2/9 = 6/9

This means 3/9 were Flounders ( 3/9 + 6/9 = 9/9 = 1)

3/9 can be reduced to 1/3.

1/3 of the fish were Flounders.

Divide the amount of flounders by the portion caught:

12 / 1/3 = 12 * 3/1 = 36 total fish.

Now you have total number of fish, multiply the total by each portion for each type of fish.

Total fish = 36

Herring = 4/9 x 36 = 16

Salmon = 2/9 x 36 = 8

6 0

3 years ago

Find the common difference for the sequence shown 1/4,5/16,3/8

Vladimir79 [104]

<span>common difference for the sequence = 1/16

cause
1/4 = 4/16
and
3/8 = 6/16

so
4/16 + 1/16 = 5/16
5/16 + 1/16 = 6/16

</span>

4 0

4 years ago

1. Write an algebraic expression for nine times of the square of a number.

Andreas93 [3]

Answer:

The algebraic expression you are looking for is:

x^2*9

7 0

3 years ago

Use the quadratic formula to solve each equation.

Elden [556K]

Answer:

1) $x_1 = \frac{2 - 2\sqrt{13}}{2}= 1-\sqrt{13}$

$x_2 = \frac{2 + 2\sqrt{13}}{2}= 1+\sqrt{13}$

2) $x_1 = \frac{6 - 2\sqrt{10}}{1}= 6-2\sqrt{10}$

$x_2 = \frac{6 + 2\sqrt{10}}{1}= 6+2\sqrt{10}$

3) $p_1 = \frac{-8 - 2\sqrt{30}}{4}= -2-\frac{1}{2}\sqrt{30}$

$p_2 = \frac{-8 + 2\sqrt{30}}{4}= -2+\frac{1}{2}\sqrt{30}$

4) $y_1 = \frac{-3 - 9}{4}=-3$

$y_2 = \frac{-3 + 9}{4}= \frac{3}{2}$

Step-by-step explanation:

The quadratic formula is given by:

$x = \frac{-b \pm \sqrt{b^2 -4ac}}{2a}$

We can use this formula in order to solve the following equations:

1. x^2 − 2x = 12 → a = 1, b = −2, c = −12

For this case if we apply the quadratic formula we got:

$x = \frac{-(-2) \pm \sqrt{(-2)^2 -4(1)(-12)}}{2(1)}$

$x_1 = \frac{2 - 2\sqrt{13}}{2}= 1-\sqrt{13}$

$x_2 = \frac{2 + 2\sqrt{13}}{2}= 1+\sqrt{13}$

2. 1/2x^2 − 6x = 2 → a = 1 / 2, b = −6, c = −2

For this case if we apply the quadratic formula we got:

$x = \frac{-(-6) \pm \sqrt{(-6)^2 -4(1/2)(-2)}}{2(1/2)}$

$x_1 = \frac{6 - 2\sqrt{10}}{1}= 6-2\sqrt{10}$

$x_2 = \frac{6 + 2\sqrt{10}}{1}= 6+2\sqrt{10}$

3. 2p^2 + 8p = 7 → a = 2, b = 8, c = −7

For this case if we apply the quadratic formula we got:

$p = \frac{-(8) \pm \sqrt{(8)^2 -4(2)(-7)}}{2(2)}$

$p_1 = \frac{-8 - 2\sqrt{30}}{4}= -2-\frac{1}{2}\sqrt{30}$

$p_2 = \frac{-8 + 2\sqrt{30}}{4}= -2+\frac{1}{2}\sqrt{30}$

4. 2y^2 + 3y − 5 = 4 → a = 2, b = 3, c = −9

For this case if we apply the quadratic formula we got:

$y = \frac{-(3) \pm \sqrt{(3)^2 -4(2)(-9)}}{2(2)}$

$y_1 = \frac{-3 - 9}{4}=-3$

$y_2 = \frac{-3 + 9}{4}= \frac{3}{2}$

8 0

4 years ago

Hi there can anyone help me

SIZIF [17.4K]

The answer is 39 if rounded it is 40

7 0

4 years ago