Answer:
p=1
Step-by-step explanation:
A deck has a combined 52cards.
Given that you're certain to select a red or black card:-
p(red)=>
p(black)=>
Therefore total probability of selection is expressed as:-

Knowing the squareroot of 81 is 9, we can easily know that square root of 83 is close to 9.
9 to the closest tenth is 10.
Hope I helped :)
Sum of complement angles = 90
<L + <M = 90
3x - 15 + x = 90
4x - 15 = 90
4x = 105
x = 26.25
<L = 3(18.5) - 15
<L = 63.75
Answer
<L = 63.75°