All categories

3 years ago

How do you solve x^2 plus 16x plus 63=0?

1 answer:

Alex3 years ago

8 0

$x^2+ 16x + 63=0 \\ \\a=1, \ b=16 , \ c=63 \\ \\ \Delta =b^2-4ac =16^2 -4\cdot1\cdot 63 = 256 -252 = 4 \\ \\x_{1}=\frac{-b-\Delta }{2a}=\frac{-16-\sqrt{4}}{2 }=\frac{-16-2}{2}=-\frac{-18}{2}=-9 \\ \\x_{2}=\frac{-b+\Delta }{2a}=\frac{-16+\sqrt{4}}{2 }=\frac{-16+2}{2}=-\frac{-14}{2}=-7 \\ \\ \\Answer : \ x= -7 \ \ or \ \ x= -9$

You might be interested in

How do you write an equation of a line in standard form if you have two points?

ziro4ka [17]

First find the slope using the slope formula M= (y2-y1) divided by (x2-x1) and then take the slope and and the 1st set of points (x1, y1) and plug it into the slope intercept formula which is y-y1=m(x-x1), then you need to add or subtract variables to correlate with the standard form formula which is ax + by = c.
Hope that helps!

3 0

4 years ago

The smallest prime factor of twelve is

Nimfa-mama [501]

2 is your prime factor

6 0

3 years ago

In Δ ABC and ΔXYZ ,∠B=∠X=90 and BC=XZ .What additional information is required to make Δ ABC congruent to ΔXYZ by R.H.S conditio

Pani-rosa [81]

Answer:

AC = XY

Step-by-step explanation:

A triangle is a polygon with three sides and three angles. The types of triangles are scalene triangle, equilateral triangle, right angled triangle and obtuse triangle.

Two triangles are said to be congruent if all the three sides and three angles of one triangle is equal to the three sides and three angles of the other triangle.

In Δ ABC and ΔXYZ ,∠B=∠X=90. This means that triangle ABC and triangle XYZ are right angled triangle since one of their angles is 90 degrees.

The hypotenuse is the side opposite to right angle (90 degrees).

Therefore AC is the hypotenuse of triangle ABC and YZ is the hypotenuse of triangle XYZ.

If the hypotenuse and one leg of a right angled triangle is equal to the hypotenuse and leg of another right angled triangle, then the two triangles are congruent by RHS rule.

Since BC = XY, for Δ ABC congruent to ΔXYZ by R.H.S condition, the hypotenuse have to be equal, i.e. AC = XY

7 0

3 years ago

What percentage is 15 out of 17?

Ket [755]

88.23%

Simply plug 15/17 into you calculator

and it will give you a decimal, in this case it should be .88235294...

simply move the decimal back to placements and you should have

88.235294... thats still a lot of numbers so just reduce it to 2 places after the decimal and add a percent sign

88.23%

and your done :) this works for any similar problems

I hope this helps

8 0

3 years ago

Read 2 more answers

A 60-kg skier starts from rest from the top of a 50-m high slope. If the work done by friction is -6.0 kJ, what is the speed of

Fofino [41]

Answer:

31 m/s

Step-by-step explanation:

In order to find the speed of the skier at the bottom of the slope, you have to apply the Work-Energy Principle for mechanical energy.

W ncf= ΔEm

Where ΔEm is the variation of mechanical energy between two points of the displacement and Wncf is the work of all non-conservative forces.

The only non-conservative force producing work is the friction force. The normal force doesn't produce work because it's perpendicular to the displacement.

The variation of the mechanical energy can be considered from the top to the bottom of the slope.

Wncf= Emf-Emi

Where Emf is the final mechanicl energy and Emi is the initial mechanical energy.

The mechanical energy is defined by:

Em= Ep+Ek

Where Ep is the potential energy and Ek is the kinetic energy.

At the top of the slope, there's only potential gravitational energy (the kinetic energy is zero because the skier starts from rest)

Emi=Ep= mgh

m=60 kg, g=9.8 m/s² and h=50 m

Emi= 29400 J

At the bottom of the slope, there's only kinetic energy (the potential gravitational energy is zero because the height is zero)

Emf= Ek = 1/2mv² =30v²

where v is the speed and m is the mass.

Replacing in the equation:

-6.0 = 30v² - 29400

Solving for v (Adding 29400, dividing by 30, extracting the square root)

v=31.3 m/s

7 0

3 years ago