book Maths Puzzle Numerical Ability

I am stumped on this question. Can someone please help me with it.

Find the equation, in standard form, including all integer coefficients, of the line perpendicular to 3x - 4y = 9 and passing through (-2, -1).

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book Other Question
World grain demand. Freeport McMoRan projects that in 2010 world grain supply will be 1.8 trillion metric tons and the supply will be only 3/4 of world grain demand. What will world grain demand be in 2010? Can someone help me with these two problems?
(1)
Add. Write the answer in the lowest terms.

3/8 + 5/8
(2)
Add. Write the answer in lowest terms.
5/9 + 8/9
Thank you.