Answer:
. . . 18. x = 8√6
. . . 19. x = 3
. . . 20. x = 3√3
. . . 21. x = 5/3
Step-by-step explanation:
You have already marked the correct relationships on the drawings. Finding the value of x is a matter of making use of those relationships.
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18. As you show, x is the given side multiplied by √3, so is ...
. . .x = (8√2)(√3) = 8√6
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19. As you show, the given side is x multiplied by √2, so ...
. . . 3√2 = x√2
. . . 3 = x . . . . . . . . . . divide by √2
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20. As you show, the given side is x multiplied by √3, so ...
. . . x√3 = 9
. . . x = 3√3 . . . . . . multiply by (√3)/3
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21. As you show, ...
. . . 8x -10 = 2x
. . . 6x -10 = 0 . . . . . subtract 2x
. . . x - 10/6 = 0 . . . . divide by 6
. . . x = 5/3 . . . . . . . . reduce the fraction and add it to both sdes
