I need help on this question

the answer is 3.81

but rounding it it will be 3.8 meters

Step-by-step explanation:

Pythagorean theorem says

a²+b²=c²

so,

take take the Lowest measurement as a² which will be 7 and take 8 as the hypotenuse or the longest side which is c²

then put it all together you get

7²+x²=8²

we made b as x because we will be finding b

then substitute the values

x²=8²-7²

x²=64-49

x²=15

to remove that square from the x you then put square root in both

✓x²=✓15

press in the calculator, root of 15 will be about 3.81

now we got

x=3.81

x is the missing measurement