45 is what percent of 60

A jet travels 500 miles in 5 hours. What is the ratios of miles to hours?

tia_tia [17]

Answer:

different answers in step-by-step

Step-by-step explanation:

100 mph

100mi:1hr

100mi/1hr

3 0

2 years ago

At what point on the paraboloid y = x2 + z2 is the tangent plane parallel to the plane 3x + 2y + 7z = 2? (if an answer does not

Nikitich [7]

If $f(x, y, z) = c$ represent a family of surfaces for different values of the constant $c$ . The gradient of the function $f$ defined as $\nabla f$ is a vector normal to the surface $f(x, y, z) = c$ .

Given the paraboloid

$y = x^2 + z^2$ .

We can rewrite it as a scalar value function f as follows:

$f(x,y,z)=x^2-y+z^2=0$

The normal to the paraboloid at any point is given by:

$\nabla f= i\frac{\partial}{\partial x}(x^2-y+z^2) - j\frac{\partial}{\partial y}(x^2-y+z^2) + k\frac{\partial}{\partial z}(x^2-y+z^2) \\ \\ =2xi-j+2zk$

Also, the normal to the given plane $3x + 2y + 7z = 2$ is given by:

$3i+2j+7k$

Equating the two normal vectors, we have:

$2x=3\Rightarrow x= \frac{3}{2} \\ \\ -1=2 \\ \\ 2z=7\Rightarrow z= \frac{7}{2}$

Since, -1 = 2 is not possible, therefore there exist no such point on the paraboloid $y = x^2 + z^2$ such that the tangent plane is parallel to the plane 3x + 2y + 7z = 2.

4 0

3 years ago

Just number 9 would be fine please but also if you could number 10 would help

topjm [15]

Answer:

9. a = -7

10. x = 1

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Equality Properties

Step-by-step explanation:

Step 1: Define equation

a + 6a - 14 = 3a + 6a

Step 2: Solve for a

Combine like terms: 7a - 14 = 9a
Subtract 7a on both sides: -14 = 2a
Divide 2 on both sides: -7 = a
Rewrite: a = -7

Step 3: Check

Plug in a into the original equation to verify it's a solution.

Substitute in a: -7 + 6(-7) - 14 = 3(-7) + 6(-7)
Multiply: -7 - 42 - 14 = -21 - 42
Subtract: -49 - 14 = -63
Subtract: -63 = -63

Here we see that -63 is equal to -63.

∴ a = -7 is a solution of the equation.

Step 4: Define equation

-12 - 4x = 8x + 4(1 - 7x)

Step 5: Solve for x

Distribute 4: -12 - 4x = 8x + 4 - 28x
Combine like terms: -12 - 4x = -20x + 4
Add 20x on both sides: -12 + 16x = 4
Add 12 on both sides: 16x = 16
Divide 16 on both sides: x = 1

Step 6: Check

Plug in x into the original equation to verify it's a solution.

Substitute in x: -12 - 4(1) = 8(1) + 4(1 - 7(1))
Multiply: -12 - 4 = 8 + 4(1 - 7)
Subtract: -16 = 8 + 4(-6)
Multiply: -16 = 8 - 24
Subtract: -16 = -16

Here we see that -16 does indeed equal -16.

∴ x = 1 is a solution of the equation.

7 0

2 years ago

The area of the rectangular sandbox at Dave's school is 117 square feet. The sandbox has a width of 9 feet as shown in the diagr

Annette [7]

Answer:

ay bru ima tell yu dhis rn is c

Step-by-step explanation:

4 0

2 years ago

Two sisters like to compete on their bike rides. Tamara can go 4 mph faster than her sister, Samantha. If it takes Samantha 1 ho

Triss [41]

Answer:

16 mph

Step-by-step explanation:

You should first form equations related to this information

Given,Tamara can go 4 mph faster than her sister, Samantha

Lets take speed to ride a bike for Samantha to be= x mph

The speed to ride a bike for Tamara will be= x+4 mph

To cover a distance of 80 miles, Samantha takes 1 hour longer than Tamara

Introduce the formula for time; time=distance/speed=D/S where D is distance in miles and S is speed in miles per hour

Here time Samantha takes to cover a distance of 80 miles is 1 hour more than that taken by Tamara, hence

Time taken by Samantha

$=\frac{80}{x}$

Time taken by Tamara

$=\frac{80}{4+x}$

Equation for difference in time

$=\frac{80}{x} -\frac{80}{4+x} =1$

Solve the equation for difference in time to get value of x which is samantha speed

$=\frac{80}{x} -\frac{80}{x+4} =1\\\\\\=80(4+x)-80(x)=x(4+x)\\\\\\=320+80x-80x=4x+x^2\\\\\\=x^2+4x-320=0$

Solve quadratic equation by the quadratic formula where a=1,b=4 and c=-320

x=(-b±√b²-4ac)÷2a

x=(-4±√4²-4×1×-320)÷2×1

$x=\frac{-4+/-\sqrt{4^2-4*1*-320} }{2} \\\\\\x=(-4+/-\sqrt{1296} )/2\\\\\\x=\frac{-4+36}{2} =\frac{32}{2} =16$

Samantha speed is 16 mph

6 0

2 years ago

45 is what percent of 60​

45 is what percent of 60