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Direct Square Variation

Example #1

a varies directly as the square of b. If a =108 when b = . !olve for a b = 8.

a = "b $ranslate the statement into a direct square variation formula

108="%& !ubstitute "nown values and brin' down the constant then square the value of b108 = ( " )ivide both sides by ( ( (

  " = ( $he value of the instant is (

  a = "b  *opy the formula  a= %(&%8&    !ubstitute the value of " and b

  a=%(&%+& !quare the value of b then multiply by the of " 

  a = 1, $herefore- the answer is 1,

Example #

r varies as the square of n. If r = 00 when n = - !olve for r when n = (.

  r = "n $ranslate the statement into a direct square formula

00 = "%& !ubstitute "nown values and brin' down the constant then square the value of b00 = " )ivide both sides by

   "=0 $he value of " is 0

r ="n copy the formular=%0&%(& !ubstitute the values of " and n

r = %0&%,& !quare the value of b then multiply by the of " 

r = 180 $he value of r is 180

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Example #(

t varies directly as the square of u. If u is increased by (0/- what happens to the value of t

t = "u $ranslate the statement into a direct square variation formula

t = " %1.( u& !ubstitute the value of u and 100/ then brin' down the constant

t = " %1., u& !quare the value of u

t = "%10.,&u !eparate the 100/ and 0.,

0., = , / *han'e 0., into percent form

t is increased by ,/