Simplify (3x + 5) + (2x - 9)

Taylor says ABCD and EFGH are congruent because he can map ABCD to EFGH by multiplying each side length by 1.5 and translating t

Elina [12.6K]

Answer:

The E came before H

Step-by-step explanation:

8 0

2 years ago

A ball slides up a frictionless ramp. It is then rolled without slipping and with the same initial velocity up another frictionl

KATRIN_1 [288]

Answer:

Rolling case achieves greater height than sliding case

Step-by-step explanation:

For sliding ball:

- When balls slides up the ramp the kinetic energy is converted to gravitational potential energy.

- We have frictionless ramp, hence no loss due to friction.So the entire kinetic energy is converted into potential energy.

- The ball slides it only has translational kinetic energy as follows:

ΔK.E = ΔP.E

0.5*m*v^2 = m*g*h

h = 0.5v^2 / g

For rolling ball:

- Its the same as the previous case but only difference is that there are two forms of kinetic energy translational and rotational. Thus the energy balance is:

ΔK.E = ΔP.E

0.5*m*v^2 + 0.5*I*w^2 = m*g*h

- Where I: moment of inertia of spherical ball = 2/5 *m*r^2

w: Angular speed = v / r

0.5*m*v^2 + 0.2*m*v^2 = m*g*h

0.7v^2 = g*h

h = 0.7v^2 / g

- From both results we see that 0.7v^2/g for rolling case is greater than 0.5v^2/g sliding case.

4 0

3 years ago

42:28

gogolik [260]

Answer:

The statements about arcs and angles that are true in the figure are;

1) ∠EFD ≅ ∠EGD

2) $\overline{ED}\cong \overline{FD}$

3) mFD = 120°

Step-by-step explanation:

1) ∠ECD + ∠CEG + ∠CDG + ∠GDE = 360° (Sum of interior angle of a quadrilateral)

∠CEG = ∠CDG = 90° (Given)

∠GDE = 60° (Given)

∴ ∠ECD = 360° - (∠CEG + ∠CDG + ∠GDE)

∠ECD = 360° - (90° + 90° + 60°) = 120°

∠ECD = 2 × ∠EFD (Angle subtended is twice the angle subtended at the circumference)

120° = 2 × ∠EFD

∠EFD = 120°/2 = 60°

∠EFD ≅ ∠EGD

∠ECD = 120°

∠EGD = 60°

∴∠EGD ≠ ∠ECD

2) Given that arc mEF ≅ arc mFD

Therefore, ΔECF and ΔDCF are isosceles triangles having two sides (radii EC and CF in ΔECF and radii EF and CD in ΔDCF

∠ECF = mEF = mFD = ∠DCF (Given)

∴ ΔECF ≅ ΔDCF (Side Angle Side, SAS, rule of congruency)

$\\ \overline{EF}\cong \overline{FD}$ (Corresponding Parts of Congruent Triangles are Congruent, CPCTC)

∠FED ≅ ∠FDE (base angles of isosceles triangle)

∠FED + ∠FDE + ∠EFD = 180° (sum of interior angles of a triangle)

∠FED + ∠FDE = 180° - ∠EFD = 180° - 60° = 120°

∠FED + ∠FDE = 120° = ∠FED + ∠FED (substitution)

2 × ∠FED = 120°

∠FED = 120°/2 = 60° = ∠FDE

∴ ∠FED = ∠FDE = ∠EFD = 60°

ΔEFD is an equilateral triangle as all interior angles are equal

$\\ \overline{EF}\cong \overline{FD}\cong \overline{ED}$ (definition of equilateral triangle)

$\overline{ED}\cong \overline{FD}$

3) Having that ∠EFD = 60° and ∠CFE = ∠CFD (CPCTC)

Where, ∠EFD = ∠CFE + ∠CFD (Angle addition)

60° = ∠CFE + ∠CFD = ∠CFE + ∠CFE (substitution)

60° = 2 × ∠CFE

∠CFE =60°/2 = 30° = ∠CFD

$\overline{CF}\cong \overline{CD}$ (radii of the same circle)

ΔFCD is an isosceles triangle (definition)

∠CFD ≅ ∠CDF (base angles of isosceles ΔFCD)

∠CFD + ∠CDF + ∠DCF = 180°

∠DCF = 180° - (∠CFD + ∠CDF) = 180° - (30° + 30°) = 120°

mFD = ∠DCF (definition)

mFD = 120°.

5 0

3 years ago

From 24 teachers to 30 teachers Find each percent increase. Round to the nearest percent

yulyashka [42]

% = (Change/Original) * 100
= (6/24) * 100
= (0.25) * 100
= 25%

5 0

3 years ago

Read 2 more answers

Amira can read 6 pages in 3 minutes. At this rate, how many pages can she read in 120 minutes? A 240 pages B 60 pages C 24 pages

kirill [66]

Answer:

A

Step-by-step explanation:

he reads 2 pages per minute multiply 120 by 2

8 0

3 years ago

Read 2 more answers

Simplify (3x + 5) + (2x - 9) - (4x + 3).