Use Coordinates to Prove Simple Geometric Theorems

Find the slope of the line.

• -2
• 2
• -1
• 1

Tags

CCSS.8.EE.B.5

Find the slope of the line.

• -5/4
• 5/4
• -4/5
• 4/5

Tags

CCSS.8.EE.B.5

Slopes of parallel lines are...

• opposite reciprocals.
• opposites.
• identical.
• always 7.

Tags

CCSS.HSG.GPE.B.5

Slopes of perpendicular lines are...

• opposite reciprocals.
• opposites.
• identical.
• always 7.

Tags

CCSS.HSG.CO.A.1

CCSS.HSG.GPE.B.5

What PROVES two lines are parallel to each other?

• opposite sides are congruent
• The slope is the same for both lines
• They look like it
• The lines have a slope that is a reciprocal of the other

how are lines perpendicular?

• same slope
• opposite reciprocal slope
• Pythagorean theorem
• distance formula

y = -2x - 4
y = 1/2 x + 7
are...

• parallel 
• perpendicular
• neither

A quadrilateral with 4 equal sides could be:

• a rectangle or a trapezoid
• a square or a rhombus
• a parallelogram or a trapezoid
• a kite or a square

To prove a rectangle you need to calculate and compare?

• all slopes
• all slopes and all side lengths
• all side lengths
• congruent slopes

To prove a parallelogram you need to calculate and compare?

• all slopes
• all slopes and all side lengths
• all side lengths
• congruent slopes