You have to find the area of the four triangles which is the perimeter of the base and multiply. It by your height and your case you have to find out if it’s a slant height.
To form an equation with the given information, we use the formula :
y = mx + b, m being the slope and b being the y-intercept.
Since it is given that the slope is -9/7, we substitute m with -9/7.
y = -9/7x + b
To find b, we will substitute the known coordinates into the equation :
At point (-7 , 4), x = -7, y = 4
4 = -9/7 (-7) + b
4 = 9 + b
b = 4 - 9
b = -5
Now we know that b = -5, we will substitute b = -5 into the equation that we found earlier, y = -9/7 x + b :
y = - 9/7x - 5
To make it more readable, we can multiply the equation by 7:
7y = -9x - 5
7y + 9x + 5 = 0
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Answer : 7y + 9x + 5 = 0
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We know, Length of Image = Length of Object * Dilation factor,
Just substitute your known values,
Length of Image = 9 * 2 = 18
In short, Your Answer would be 18 cm
Hope this helps!
