Helppppp plsssss!!!!!

Mathematics

1 answer:

denpristay [2]3 years ago

4 0

X^2 + 2x -4= 0

You need to remember one standard result

ax^2 + bx + c= 0

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

By Comparing the coefficients,

a= 1, b=2, c=-4

$x = \frac{ - 2 + - \sqrt{ {2}^{2} - 4 \times 1 \times - 4 } }{2 \times 1} \\ x = \frac{ - 2 + - \sqrt{4 + 16} }{2} \\ \\ x = \frac{ - 2 + - \sqrt{20} }{2} \\ \\ x = \frac{ - 2 + - 2 \sqrt{5} }{2} \\ \\ x = - 1 + - \sqrt{5}$

Options A ,C

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Martene got a small aquarium for her birthday. The aquarium is a right rectangular prism 18.5\,\text{cm}18.5cm18, point, 5, spac

MariettaO [177]

Answer:

14 cm.

Step-by-step explanation:

We have been given that an aquarium is a right rectangular prism 18.5 cm long and 15 cm wide. We are also told that Martene put 3885 cubic cm of water in the aquarium.

To find the depth or height of aquarium, we will use volume of rectangular prism formula.

$\text{Volume of rectangular prism}=l*w*h$ , where,

l = Length of prism,

w = Width of prism,

h = Height of prism.

Upon substituting our given values in above formula we will get,

$3885\text{ cm}^3=18.5\text{ cm}\times 15\text{ cm}\times h$

$3885\text{ cm}^3=277.5\text{ cm}^2\times h$

$\frac{3885\text{ cm}^3}{277.5\text{ cm}^2}=\frac{277.5\text{ cm}^2\times h}{277.5\text{ cm}^2}$

$14\text{ cm}=h$

Therefore, the aquarium is 14 cm deep.

7 0

3 years ago

PLEASE ANSWERRRRRRRRRRRRRRR

hoa [83]

Let $T,S$ be the number of days spent at Tahoe and San Francisco, respectively.

We don't know the values of $T$ and $S$ yet, but we know that the holiday lasted 9 days:

$T+S=9$

We also know that each day spent in Tahoe costed 350 and each day spent in San Francisco costed 475. So, the total cost of the holiday is the sum of the number of days muliplied by their cost:

$350T+475S=3650$