210 : 65
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42 : 13 is the ratio of 210mm long and 65mm wide
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<span>divide both numbers by 5</span>
Answer: Third Choice. x= 6 1/3
Step-by-step explanation:
Given
f(x) = 9x² - 54x - 19
Completing the square
3x -19
3x 1
Substitute back to the function
f(x) = (3x-19) (3x+1)
Simplify
x= 6 1/3 or -1/3
Hope this helps!! :)
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