The lines intersect at point L, so all angles have a vertex (middle letter) L so there is no angle TRL
Straight angle is a line with dot-vertex, so the straight angles are ∠RLS and ∠TLU.
∠TLS is less than 90° then it is acute angle (∠SLT is the same angle). ∠ULR is vertex angle to ∠TLS, so it's also acute angle.
Two angles adding to straight angle mean that they are both right angles or one is acute and the second is obtuse. ∠TLS is acute so ∠RLT is obtuse (they adding to ∠RLS) and ∠SLU is obtuse (they adding to ∠TLU). ∠ULS is the same angle as ∠SLU.
Yes it is possible because integers start at one, and do not include negative numbers while whole numbers are any numbers that are not a fraction or decimal.
Let w=width L= length 3w+1=l Perimeter -2(l+w) 2(W+3w+1)=42 Divide both sides by 2 W+3w+1=21 Subtract 1 W+3w=20 Add like terms 4w=20 Divide both sides by 4 W=5 The width is 5 inches
3w+1=l Input the width into the equation 3(5)+1=l 15+1=l 16=l The length of the rectangle is 16 inches
