All categories

3 years ago

Find x. Please help!

Mathematics

1 answer:

Viefleur [7K]3 years ago

5 0

Answer:

Im not good at these so maybe 105°? Sorry if its wrong

Step-by-step explanation:

You might be interested in

May someone answer me????

beks73 [17]

Answer:

$\huge\boxed{B. [1,2,3,........]}$

Step-by-step explanation:

$9x - 4 < 13 x - 7$

Combining like terms

=> $-4 + 7 < 13x-9x$

=> $3 < 4x$

Dividing both sides by 4

=> $x > \frac{3}{4}$

=> $x > 0.75$

This means that x can be any number <u>that is greater than 0.75</u>

So, The solution set = [1,2,3,........]

7 0

3 years ago

Lindy works at a pizza restaurant and gets a 10% employee discount. She knows that if she orders d drinks and a medium pizza wit

timofeeve [1]

Answer:

$17.28.

Step-by-step explanation:

In the expression, d represents the number of drinks she orders and t represents the number of toppings.

In this case, she orders 4 drinks and 3 toppings, so d = 4 and t = 3.

0.90(2.25d + 1.40t + 6)

= 0.9(2.25 * 4 + 1.4 * 3 + 6)

= 0.9(9 + 4.2 + 6)

= 0.9 * 19.2

= 17.28

So, the total cost for Lindy and her friends will be $17.28.

Hope this helps!

8 0

4 years ago

As a project manager

Nana76 [90]

Total number of hours=18 hrs
Number of engineers=3
So divide number of hours by number of engineers.
18/3=6 hours

Answer: Option A 6

5 0

4 years ago

It is known that x1 and x2 are roots of the equation x2−8x+k=0, where 3x1+4x2=29. find k.

zysi [14]

Answer:

k = 15

Step-by-step explanation:

∵ x² - 8x + k = 0 ⇒ has two roots x1 and x2

∵ ax² + bx + c = 0 has two roots

∴ The sum of roots = -b/a and the product of them = c/a

∵ a = 1 , b = -8 and c = k

∴ x1 + x2 = -(-8)/1 = 8

∴ x1 + x2 = 8 ⇒ (1)

∵ 3x1 + 4x2 = 29 ⇒ (2)

Multiply (1) by -4

∴ -4x1 - 4x2 = -32 ⇒ (3)

Add (2) and (3)

∴ -x1 = -3

∴ x1 = 3

By substituting value of x1 in (1)

∴ 3 + x2 = 8

∴ x2 = 5

∴ The roots are 3 and 5

∴ c/a = 3 × 5 = 15 ⇒ (a = 1)

∴ c = 15

∴ k = 15

4 0

3 years ago

Solve by quadratic equation

Ymorist [56]

<h2>Question :</h2>

$\tt \dfrac{x+2}{x-2} + \dfrac{x-2}{x+2} = \dfrac{5}{6}$

<h2>Answer :</h2>

$\large \underline{\boxed{\bf{x = \dfrac{\pm 2\sqrt{119}}{7}}}}$

<h2>Explanation :</h2>

$\tt : \implies \dfrac{x+2}{x-2} + \dfrac{x-2}{x+2} = \dfrac{5}{6}$

$\tt : \implies \dfrac{(x+2)(x+2) + (x-2)(x-2)}{(x-2)(x+2)} = \dfrac{5}{6}$

$\tt : \implies \dfrac{(x+2)^{2} + (x-2)^{2}}{(x-2)(x+2)} = \dfrac{5}{6}$

<u>Now, we know that</u> :

$\large \underline{\boxed{\bf{(a+b)^{2} = a^{2} + b^{2}+ 2ab}}}$
$\large \underline{\boxed{\bf{(a-b)^{2} = a^{2} + b^{2} - 2ab}}}$
$\large \underline{\boxed{\bf{(a+b)(a-b) = a^{2} - b^{2}}}}$

$\tt : \implies \dfrac{x^{2}+2^{2}+ 2 \times x \times 2 + x^{2}+2^{2} - 2 \times x \times 2 }{x^{2}-2^{2}} = \dfrac{5}{6}$

$\tt : \implies \dfrac{x^{2}+ 4 + \cancel{4x} + x^{2}+ 4 - \cancel{4x}}{x^{2}-4} = \dfrac{5}{6}$

$\tt : \implies \dfrac{x^{2} + x^{2} + 4 + 4}{x^{2}-4} = \dfrac{5}{6}$

$\tt : \implies \dfrac{2x^{2} + 8}{x^{2}-4} = \dfrac{5}{6}$

<u>By cross multiply</u> :

$\tt : \implies (2x^{2} + 8)6= 5(x^{2}-4)$

$\tt : \implies 12x^{2} + 48 = 5x^{2}-20$

$\tt : \implies 12x^{2} + 48 - 5x^{2} + 20 = 0$

$\tt : \implies 7x^{2} + 68 = 0$

$\tt : \implies 7x^{2} + 0x + 68 = 0$

<u>Now, by comparing with ax² + bx + c = 0, we have</u> :

a = 7
b = 0
c = 68

<u>By using quadratic formula</u> :

$\large \underline{\boxed{\bf{x = \dfrac{-b \pm \sqrt{b^{2} - 4ac}}{2a}}}}$

$\tt : \implies x = \dfrac{-(0) \pm \sqrt{(0)^{2} - 4(7)(68)}}{2(7)}$

$\tt : \implies x = \dfrac{0 \pm \sqrt{0 - 1904}}{14}$

$\tt : \implies x = \dfrac{\pm \sqrt{- 1904}}{14}$

$\tt : \implies x = \dfrac{\pm \sqrt{2\times 2\times 2\times 2\times 7\times 17}}{14}$

$\tt : \implies x = \dfrac{\pm \cancel{2} \times 2\sqrt{7\times 17}}{\cancel{14}}$

$\tt : \implies x = \dfrac{\pm2\sqrt{119}}{7}$

$\large \underline{\boxed{\bf{x = \dfrac{\pm 2\sqrt{119}}{7}}}}$

Hence value of $\bf x =\dfrac{\pm 2\sqrt{119}}{7}$

5 0

3 years ago

Read 2 more answers