Answer:
[tex]\frac{DE}{4} = \frac{9}{3}[/tex]
[tex]DE = 12[/tex]
Step-by-step explanation:
Given
See attachment for triangles ABC and DEF
Required
The proportion to find DE
To solve for DE, we can make use of the following equivalent ratios;
[tex]AB:DE = BC:EF[/tex]
Substitute values for AB, BC and EF
[tex]4:DE = 3:9[/tex]
Express as fractions
[tex]\frac{DE}{4} = \frac{9}{3}[/tex]
The above is the proportion to solve for DE
Solving further:
[tex]\frac{DE}{4} = 3[/tex]
[tex]DE = 4 * 3[/tex]
[tex]DE = 12[/tex]
