Well, split it into 3 shapes
21 x 10 = 210
3 x 6 = 18
2 x 6 = 12
210 + 18 + 12 = 240 square cm
imahe for more context
plzzz give me brainliest
F(x) = 2x^2 + 5x
f(3b) = 2(3b)^2 + 5(3b) = 2(9b^2) + 15b = 18b^2 + 15b
Answer:
C. –x + 8y = 56
Step-by-step explanation:
Write in standard form.
x − 8
y = −
56
This is a linear function in the slope - intercept form:
y = m x + b and we need a standard form:
a x + b y = c
y = 1/8 x + 7 / * 8 ( we will multiply both sides of equation by 8 )
8 y = x + 56
- x + 8 y = 56 / * ( - 1 )
x - 8 y = - 56
The equation is y = 1/8x + 7
Standard form equation is Ax + By = C, where A > = 0.
First eliminate the fractions by multiplying the equation by 8
8y = x + 56
Subtract x from each side
-x + 8y = 56
SInce x coeficient can't be negative multiply the equation by negative one.
x - 8y = -56
The table you drew under the question is exactly the right way to start.
-- Make a second column, next to the 6 and 7. This column will be
the actual number of each thing.
-- You know that there are 42 marbles, so write '42' in the box
next to the 6, on the 'Marbles' line.
Now you need to figure out what to write in the 'Stones' line, next to the 7.
-- Look at the 'Marbles' line. There's a 6 and then a 42.
Ask yourself: " Self ! What does the 6 have to be multiplied with to get 42 ?"
-- Whatever the answer is, drop down to the 'Stones' line,
and multiply the 7 by the same number.
The product is the total number of stones, and it goes in the box.
.
.
.
(The mystery number is 7. There are 49 stones.)