10. Kathy is making velvet bookmarkers for the nine. members of her book club. About how many
square centimeters of velvet will she need if the
dimensions of each bookmark are to be 20 cm
by 3.5 cm?

x = 25

step-by-step explanation:

a^2+b^2=c^2

7^2+24^2=c^2

49+576=625

sqrt625=25

x=25

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18

85.3-64 = 21.3

so laura has already added 85.3 grams of chocolate powder and she has gone over the amount specified in the recipe by 21.3 grams

hope i ! have a great  day!

c.) 38 blocks

mark brainliest   : )