Question
if a2 + b2 +
c2Â =Â 2(4a -5b -9c)-122 , then a-b-c = ?Solution
a2 + b2 + c2 = 2(4a -5b -9c)-122 So a2 + b2 + c2 -2×4a +2 ×5b + 2×9c +122 = 0 a2 -2×4a +16 + b2 +2 ×5b+25 +c2 +2×9c+81 = 0 So (a-4)2 +(b+5)2+(c+9)2 = 0 As we know that if x2 + y2 +z2 = 0 then x=y=z = 0 So here a-4 = 0 so a =4; b +5 = 0 so b = -5 And c+9 =0 so c = -9 So now a-b-c = 4-(-5)-(-9) = 4+5+9 = 18
85.22 of 499.98% + 299.99 ÷ 30.18 = ?
783 ÷ 42.59 × 25.86 =?
118.95 – 24.10 + (91.90 ÷ 22.89 × 12.14) = ?
What approximate value will come in place of the question mark (?) in the following question?(Note: You are not expected to calculate the exact value.)<...
(31.9)3 + (34.021)² - (16.11)3 - (42.98)² = ?
? = 16.08 + 13.99 × 25.07
(23.99)2 – (17.99)2 + (1378.88 + 44.88) ÷ ? = 607.998
25.31% of 5199.90 + (19.9 × 17.11) + 46.021 =? + 168.98
What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exact value.)...
?% of (144.31 ÷ 17.97 × 60.011) = 239.98
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