Answer:
![x=21.75](https://img.qammunity.org/2021/formulas/mathematics/middle-school/km4i90t7j0drqnwnzxnlqphrnayjzl1nzb.png)
Explanation:
You need to convert from mixed number to decimal number. To do this you can follow the steps shown below:
Step 1: You must divide the numerator of the fraction by the denominator of the fraction.
Step 2: Now you must add the quotient obtained to the Whole number part.
So, you get:
![7(1)/(4)=7+0.25=7.25](https://img.qammunity.org/2021/formulas/mathematics/middle-school/3kv8th6786i1b0hi7dr4ojoz6sar7t74yv.png)
Then, the scale image that maps "Figure a" onto "Figure b" is:
![1:7.25](https://img.qammunity.org/2021/formulas/mathematics/middle-school/p02wmf4nwqsze51u4wei4m0zffoy7wya80.png)
Finally, in order to find the value of "x", you need to multiply the given length of the corresponding side of "Figure a" by
.
Therefore, you get that the result is:
![x=(3)(7.25)\\\\x=21.75](https://img.qammunity.org/2021/formulas/mathematics/middle-school/zn9zbfug079lblieg9qj4ieo136nsdmipl.png)