PLEASE HELP!! i will give brainliest!

21.

The angle has an opposite side of value 11 and an adjacent side of value x

We can then apply the formula tan 38° = opposite / adjacent

this gives us tan(38) = 11 / x

11/x = tan(38)

11 = x × tan(38)

x = 11 / tan(38)

x ≈ 14.1 (rounded to the nearest tenth)

And then we need to find the length of the hypotenuse, applying the theorem of Pythagoras. Let H be the hypotenuse, then :

H² = 14,1² + 11²

H² = 198,81 + 121

H = √(319,81)

H ≈ 17,9

Finally the area of the triangle will be (17,9 + 11) / 2 = 28,9 / 2 ≈ 14,45

You apply the same thing for 22 and 23

For 22 you use tan 55 = 15 / x

For 23 you use tan 23 = 7 / x

Good Luck !

the largest number of the four options is 1.8 x 10-2

you have it in scientific notation.

1.80 x 10-6   = 0.00000180

1.80 x 10-4   = 0.000180 (bigger, or "less small", than the former one)

so

1.8 x 10-2       = 0.0180. as you see. the "less small", or the biggest one of them all.

as you have negative exponent, it means you are dividing 1.8 by 100 (i.e. moving the dot towards left, two times).

if you had positive exponent for the scientific notation, power of tenths, you would be multiplying times 100 (moving the dot towards right) as below:

1.8 x (10)2 = 180

so. if you have negative exponent in scientific notation, move the dot toward left. if it is positive, toward right as many times the exponent tells you.