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2 years ago

solve the equation x +4x-7=0 by completing the square. give your answers correct to two decimal places

Mathematics

1 answer:

olga2289 [7]2 years ago

6 0

Answer:

X= 1.4 OR 7/5 OR 1 2/5

Step-by-step explanation:

x+4x-7=0 (First, Combine Like Terms)

5x-7=0 (Then, Add 7 to both sides)

+7 +7

5x=7 (Now, divide both sides by 5)

/5 /5

You get X= 1.4 OR 7/5 OR 1 2/5

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Can someone help?

babymother [125]

Answer:

0, 3, 8, 15, 24
y = x² + 2x

Step-by-step explanation:

The pattern is

Step 1 ⇒ 1*3 = 3
Step 2 ⇒ 2*4 = 8
Step 3 ⇒ 3*5 = 15

Next step would be

Step 4 ⇒ 4*6 = 24

Step zero would be

Step 0 ⇒ 0*2 = 0

The equation

y = x(x + 2) = x² + 2x

6 0

3 years ago

Read 2 more answers

Write the equation of the line given the slope and a point through the line passes

Anuta_ua [19.1K]

Answer:

1.) Y = 5/3 X + 4

2.) Y = 9/4 X - 27/4

Step-by-step explanation:

Given the slope and the coordinate, linear equation of a line can be expressed by using general linear equation. Which is

Y = MX + C

Where the

Slope M = 5/3

Coordinate = (-3,-1) in which

X = -3, Y = -1

Substitute X, Y and M into the general linear equation to achieve C

-1 = 5/3(-3) + C

-1 = - 5 + C

C = 5 - 1

C = 4

Substitute C and M back into the general linear equation.

Therefore, the equation of the line given the slope and a point through the line passes 5/3, and (-3,-1) to be

Y = 5/3 X + 4

2.) Also,

Slope M = 9/4

Coordinate = (3,0) where X = 3, Y = 0

Substitute X, Y and M into the general linear equation to obtain C

0 = 9/4 (3) + C

C = - 27/4

Substitutes C and M back into the general linear equation

Therefore, the equation of the line given the slope and a point through the line passes 9/4 and (3,0)

Y = 9/4 X - 27/4

4 0

2 years ago

Select all of the correct solutions for the following equation

zhuklara [117]

Answer: a,b, and c are the correct solutions

Step-by-step explanation:

You are substituting each (x,y) for the equation given. They must equal the same on both sides.

5 0

2 years ago

Solve these inequalities by showing all steps of working b) 5x + 4 < 16 *

Mama L [17]

Step-by-step explanation:

5x+4<16

or,5x<16-4

or,5x<12

or,x<12÷5

or,x<12/5

or,x<2.4

:.x<2.4

6 0

3 years ago

Read 2 more answers

An ice cube is melting, and the lengths of its sides are decreasing at a rate of 0.8 millimeters per minute At what rate is the

julia-pushkina [17]

Answer:

The rate of decrease is: $43.2mm^3/min$

Step-by-step explanation:

Given

$l = 18mm$

$\frac{dl}{dt} = -0.8mm/min$ ---- We used minus because the rate is decreasing

Required

Rate of decrease when: $l = 18mm$

The volume of the cube is:

$V = l^3$

Differentiate

$\frac{dV}{dl} = 3l^2$

Make dV the subject

$dV = 3l^2 \cdot dl$

Divide both sides by dt

$\frac{dV}{dt} = 3l^2 \cdot \frac{dl}{dt}$

Given that: $l = 18mm$ and $\frac{dl}{dt} = -0.8mm/min$

$\frac{dV}{dt} = 3 * (18mm)^2 * (-0.8mm/min)$

$\frac{dV}{dt} = 3 * 18 *-0.8mm^3/min$

$\frac{dV}{dt} = -43.2mm^3/min$

Hence, the rate of decrease is: 43.2mm^3/min

8 0

3 years ago