check it out! 1 1.7.2: working with ratio segments
TRANSCRIPT
Landscapers will often stake a sapling to strengthen the tree’s root system. A typical method of staking a tree is to tie wires to both sides of the tree and then stake the wires to the ground. If done properly, the two stakes will be the same distance from the tree.
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1.7.2: Working with Ratio Segments
1. Assuming the distance from
the tree trunk to each stake
is equal, what is the value of x?
2. How far is each stake from the tree?
3. Assuming the distance from the tree
trunk to each stake is equal, what is
the value of y?
4. What is the length of the wire from
each stake to the tie on the tree?
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1.7.2: Working with Ratio Segments
2y + 17
7y – 3
4x – 5 2x + 1
1. Assuming the distance from the tree trunk to each stake is equal, what is the value of x?• To find the value of x, set both expressions equal
to each other.
• The value of x is 3.4
1.7.2: Working with Ratio Segments
Set the expressions equal to each other.
Subtract 2x from both sides of the equation.
Add 5 to both sides of the equation.
Divide both sides by 3.
2x = 6
x = 3
4x – 5 = 2x + 1
2x – 5 = 1
2. How far is each stake from the tree?• To determine how far each stake is from the tree,
substitute 3 for x in either expression.
• Each stake is 7 units from the tree trunk.5
1.7.2: Working with Ratio Segments
Original expression
Substitute 3 for x.
Simplify.12 – 5 = 7
4x – 5
4(3) – 5
Original expression
Substitute 3 for x.
Simplify.6 + 1 = 7
2x + 1
2(3) + 1
3. Assuming the distance from the tree trunk to each stake is equal, what is the value of y?• To find the value of y, set both expressions equal
to each other.
• The value of y is 4.6
1.7.2: Working with Ratio Segments
Set the expressions equal to each other.
Subtract 2y from both sides of the equation.
Add 3 to both sides of the equation.
Divide both sides by 5.
20 = 5y
y = 4
2y + 17 = 7y – 3
17 = 5y – 3
4. What is the length of the wire from each stake to the tie on the tree?• To determine the length of the wire from each
stake to the tie on the tree, substitute 4 for y in each expression.
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1.7.2: Working with Ratio Segments
• The length of the wire from each stake to the tie on the tree trunk is 25 units.
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1.7.2: Working with Ratio Segments
Original expression
Substitute 4 for y.
Simplify.8 + 17 = 25
2y + 17
2(4) + 17
Original expression
Substitute 4 for y.
Simplify.28 – 3 = 25
7y – 3
7(4) – 3