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3 years ago

What number must be added to the expression below to complete the square ? x2+7x

Mathematics

1 answer:

stellarik [79]3 years ago

6 0

Answer:

you must add 2 to the equation

Step-by-step explanation:

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Division need help help me know what 12 ÷ 4 =

notsponge [240]

12/4 is 3, and you can check this because 3 x 4 is 12.

3 0

4 years ago

Read 2 more answers

X— 3y+z= 6<br>2x — бу – 2 = -2<br>—x+y+ 2 = 7

dlinn [17]

Answer:

x = -7 1/2

y = - 5/2

z = 11

Step-by-step explanation:

x— 3y+z= 6 (1)

2x — бу – 2 = -2 (2) <=> 2x - 6y = -2 + 2 = 0 <=> (2x - 6y)/2 = 0 <=> x - 3y = 0 (4)

—x+y+ 2 = 7 (3) <=> -x + y = 7 - 2 <=> x - y = -5 (5)

Subtract (5) from (4), we have:

(x - 3y) - (x - y ) = 0 - (-5)

<=> x - 3y - x + y = 5

<=> -2y = 5

<=> y = - 5/2

Replace y with (4), we have x = 3 × (-5/2) = -15/2 (or -7 1/2)

Replace x with -15/2 and y with -5/2 in (1), we have z = 6 - (-15/2 - (-5/2)) = 6 + (15/2 - 5/2) = 6 + 5 = 11

4 0

3 years ago

Read 2 more answers

Rhett is solving the quadratic equation 0= x2 – 2x – 3 using the quadratic formula. Which shows the correct substitution of the

lesya692 [45]

Answer:

The correct option is 1.

Step-by-step explanation:

If a quadratic equation is defined as

$ax^2+bx+c=0$

then the quadratic formula is

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

The given equation is

$0=x^2-2x-3$

Here, a=1, b=-2 and c=-3.

Substitute these values in the above formula.

$x=\frac{-(-2)\pm \sqrt{(-2)^2-4(1)(-3)}}{2(1)}$

$x=\frac{2\pm \sqrt{(-2)^2-4(1)(-3)}}{2(1)}$

Therefore, the correct option is 1.

4 0

4 years ago

Bess [88]

Answer:

Show the whole pic

Step-by-step explanation:

6 0

3 years ago

Two thirds of a number reduced by 11 is equal to 4 more than the numher. find the number

Anika [276]

Answer:

- 45

Step-by-step explanation:

let n be the number , then

$\frac{2}{3}$ n - 11 = n + 4 ( add 11 to both sides )

$\frac{2}{3}$ n = n + 15 ( multiply through by 3 to clear the fraction

2n = 3n + 45 ( subtract 2n from both sides )

0 = n + 45 ( subtract 45 from both sides )

- 45 = n

The number is - 45

8 0

3 years ago

Read 2 more answers