Using words or pictures, explain how you would use the sum 13 to show how to add in any number

What is the value of x when x + 7 = 21?

Worth 100 points need the answers asap first row -x^2 2x^2 (x/2)^2 x^2 x is less than 2 x is greater than 2 x is less than or equal to 2 x is greater than or equal to 2 second row -5 -5/2 4 5 •2 is less than x& x is less than 4 •2 is less than or equal to x & x is less than or equal to 4 •2 is less than or equal to x& x is less than 4 •2 is less than x& x is less than or equal to 4

If cos(θ)=2853 with θin q iv, what is sin(θ)?