For the first one, we know that is a right angle. right angles are 90 degrees. if we subtract 90 - 49 that equals 41. so the second value needs to equal 41. since we have a 3 there already, we are going to subtract 41-3, which is 38. x = 38
I hope this helps you
Area=length.width
343=l.w
7.7.7=l.w
l=49
w=7
Perimeter=2 (49+7)
Perimeter=2.56
Perimeter=112
