Answer:
11.since diagonal are equal of rectangle
QS=RT
4x+6=6x-4
6+4=6x-4x
2x=10
x=10/2
x=5
now
diagonal :4x+6=4*5+6=<u>26</u>
12.
again
QS=RT
9x+12=11x-10
12+10=11x-9x
2x=22
x=11
now
diagonal=9*11+12=99+12=<u>111</u>
The error is that the student measured the wrong side. Acute angles are less than 90 degrees. So it isn’t possible for the measure to be over 90. The correct measure is 49
9x - 2 = 67
67 + 2 = 69
69 × 9 = 621
621 = x