Decimal equivalent to. 78/11

Solve: x2 + 8x - 9 = 0 please i need it urgently

Likurg_2 [28]

Answer:

x = 1 or x = -9

Step-by-step explanation:

Solve for x over the real numbers:

x^2 + 8 x - 9 = 0

Hint: | Solve the quadratic equation by completing the square.

Add 9 to both sides:

x^2 + 8 x = 9

Hint: | Take one half of the coefficient of x and square it, then add it to both sides.

Add 16 to both sides:

x^2 + 8 x + 16 = 25

Hint: | Factor the left hand side.

Write the left hand side as a square:

(x + 4)^2 = 25

Hint: | Eliminate the exponent on the left hand side.

Take the square root of both sides:

x + 4 = 5 or x + 4 = -5

Hint: | Look at the first equation: Solve for x.

Subtract 4 from both sides:

x = 1 or x + 4 = -5

Hint: | Look at the second equation: Solve for x.

Subtract 4 from both sides:

Answer: x = 1 or x = -9

6 0

3 years ago

The answer for this system

Natali [406]

Consider this option:
$\left \{ {{y=3x-4} \atop {2x+3y=21}} \right. \ =\ \textgreater \ \ \left \{ {{y=3x-4} \atop {2x+3(3x-4)=21}} \right. \ =\ \textgreater \ \ \left \{ {{y=3x-4} \atop {11x=33}} \right. \ =\ \textgreater \ \ \left \{ {{x=3} \atop {y=5}} \right.$

answer: (3;5).

8 0

3 years ago

The inequality of the graph

fiasKO [112]

Answer:

$\displaystyle y > 4x - 2$

Step-by-step explanation:

Starting from the y-intercept of $\displaystyle [0, -2],$ you do $\displaystyle \frac{rise}{run}$ by either moving four blocks south over one block west or four blocks north over one block east [west and south are negatives]. Next, we have to determine the types of inequality symbols that are suitable for this graph, which will be less than and greater than since this is a dashed line graph. We then use the zero-interval test [test point (0, 0)] to ensure whether we shade the opposite portion [portion that does not contain the origin] or the portion that DOES contain the origin. At this step, we must verify the inequalities as false or true:

Greater than

$\displaystyle 0 > 4[0] - 2 → 0 > -2$ ☑

Less than

$\displaystyle 0 < 4[0] - 2 → 0 ≮ -2$

This graph is shaded in the portion of the origin, so you would choose the greater than inequality symbol to get this inequality:

$\displaystyle y > 4x - 2$

I am joyous to assist you anytime.

3 0

4 years ago

When using Cramer's Rule to solve a system of equations, if the determinant of the coefficient matrix equals zero and at least o

Ainat [17]

Answer:

B. is dependent

Step-by-step explanation:

The denominator determinant will be zero when the coefficients of the variables are dependent. One of the numerator coefficients will be zero when the coefficients involved are dependent. Hence using Cramer's Rule will result in the ratio 0/0 when the system is dependent.

___

The ratio will be 1/0 if the system is inconsistent (has no solution).

7 0

3 years ago

After two months of living at his new apartment, Henry had two cats. Six months later, Henry still had two cats. Which of the gr

marysya [2.9K]

The 2 graph models cat population because as it says the cat has been with it after 6 months and it stays the same

5 0

4 years ago