I think that first you need to understand what CPCTC is used for.
Let's start with the definition of congruent triangles.
Definition of congruent triangles
Two triangles are congruent if each side of one triangle is congruent to a corresponding side of the other triangle and each angle of one triangle is congruent to a corresponding angle of the other triangle.
A definition works two ways.
1) If you are told the sides and angles of one triangle are congruent to the corresponding sides and angle of a second triangle, then you can conclude the triangles are congruent.
2) If you are told the triangles are congruent, then you can conclude 6 statements of congruence, 3 for sides and 3 for angles.
Now let's see what CPCTC is and how it works.
CPCTC stands for "corresponding parts of congruent triangles are congruent."
The way it works is this. You can prove triangles congruent by knowing fewer that 6 statements of congruence. You can use ASA, SAS, AAS, SSS, etc. Once you prove two triangles congruent, then by the definition of congruent triangles, there are 6 congruent statements. That is where CPCTC comes in. Once you prove the triangles congruent, then you can conclude two corresponding sides or two corresponding angles are congruent by CPCTC. These two corresponding parts were not involved in proving the triangles congruent.
Problem 1.
Statements Reasons
1. Seg. AD perp. seg. BC 1. Given
2. <ADB & <ADC are right angles 2. Def. of perp. lines
3. <ADB is congr. <ADC 3. All right angles are congruent
4. Seg. BD is congr. seg CD 4. Given
5. Seg. AD is congr. seg. AD 5. Congruence of segments is reflexive
6. Tr. ABD is congr. tr. ACD 6. SAS
7. Seg. AB is congr. seg. AC 7. CPCTC
Footballs : basketballs = 2.5 : 1
(x 2)
footballs : basketballs = 5 : 2
⇒ basketballs : footballs = 2 : 5
Answer: <span>The ratio of basketballs to footballs is 5 : 2.</span>
The unit rate is -1/3.
In direct variation, y varies directly to x by a constant ratio k.
Its equation looks like this: y = kx ; where k stands for the constant ratio.
In the above equation. x = -3y, it should be converted to the proper equation. both sides must be transferred and its accompanying sign must be changed.
3y = -x
3y/3 = -x/3
y = (-1/3)x
where: y is the total value; -1/3 is the unit rate; and x is the number of units
Answer:
Step-by-step explanation:
find the slope 1/2
then write it as y-4=1/2(x+6)
then u get y=1/2x+7
Answer:
Percentage of error by Clare is estimated as 4.1667 %
Step-by-step explanation:
Height measured by Clare = 4 feet
Height measured by Doctor = 4 feet, 2 inches
Percentage error = ?
Percentage error = Difference/ Actual height *100
Percentage error = (2/ (4*12))*100
Percentage error = 4.1667 %
The accurate height is measured by Doctor, as he have more accurate measurement system.