Respuesta :
Answer: The length of BC is: " 20 cm " .
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Explanation:
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[AC] / [DF] = 12 cm / 9 cm ;
[BC] / [EF] = x / 15 cm ;
12 / 9 = x / 15 ; Solve for "x" ; {Note: "x" is the length of BC (in cm) ;
Simplify the " (12/9) " ;
→ " 12 / 9 = (12 ÷ 3) / (9 ÷ 3) " ;
= 4 / 3 ;
And rewrite:
→ 4 / 3 = x / 15 ; Solve for "x" ;
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Note: Cross-multiply:
Given: "(a/b)" = (c/d)" ; { b[tex] \neq [/tex]0 ; d[tex] \neq [/tex]0 } ;
" a*d = b*c " .
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As such:
→ 3x = 15 * 4 ;
→ 3x = 60 ;
Divide EACH SIDE of the equation by "3" ;
to isolate "x" on one side of the equation; & to solve for "x" ;
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→ 3x / 3 = 60 / 3 ;
→ x = 20 .
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Answer: The length of BC is: " 20 cm " .
____________________________________________________
____________________________________________________
Explanation:
____________________________________________________
[AC] / [DF] = 12 cm / 9 cm ;
[BC] / [EF] = x / 15 cm ;
12 / 9 = x / 15 ; Solve for "x" ; {Note: "x" is the length of BC (in cm) ;
Simplify the " (12/9) " ;
→ " 12 / 9 = (12 ÷ 3) / (9 ÷ 3) " ;
= 4 / 3 ;
And rewrite:
→ 4 / 3 = x / 15 ; Solve for "x" ;
_____________________________________________________
Note: Cross-multiply:
Given: "(a/b)" = (c/d)" ; { b[tex] \neq [/tex]0 ; d[tex] \neq [/tex]0 } ;
" a*d = b*c " .
_____________________________________________________
As such:
→ 3x = 15 * 4 ;
→ 3x = 60 ;
Divide EACH SIDE of the equation by "3" ;
to isolate "x" on one side of the equation; & to solve for "x" ;
__________________________________________________
→ 3x / 3 = 60 / 3 ;
→ x = 20 .
____________________________________________________
Answer: The length of BC is: " 20 cm " .
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The triangle ABC and triangle DEF are similar so the value of the length of BC is 20 cm and this can be determined by using the properties of a similar triangle.
Given :
- Triangle ABC is similar to triangle DEF.
- The length of AC is 12 cm.
- The length of EF is 15 cm.
- The length of DF is 9cm.
The following steps can be used to determine the length of BC:
Step 1 - According to the given data, triangle ABC is similar to triangle DEF.
Step 2 - So, according to step 1:
[tex]\rm \dfrac{AC}{DF} = \dfrac{BC}{EF}[/tex]
Step 3 - Substitute the values of length AC, DF, and EF in the above equation.
[tex]\rm \dfrac{12}{9} = \dfrac{BC}{15}[/tex]
Step 4 - Multiply 15 on both sides in the above expression.
[tex]\rm \dfrac{12}{9}\times 15 = BC[/tex]
Step 5 - Simplify the above expression in order to get the value of the length BC.
BC = 20 cm
For more information, refer to the link given below:
https://brainly.com/question/19237987