Answer:
x ≈ - 5.32, x ≈ 1.32
Step-by-step explanation:
Given
x² + 4x - 7 = 0 ( add 7 to both sides )
x² + 4x = 7
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(2)x + 4 = 7 + 4
(x + 2)² = 11 ( take the square root of both sides )
x + 2 = ± 
( subtract 2 from both sides )
x = - 2 ±
Thus
x = - 2 - ≈ - 5.32 ( to 2 dec. places )
x = - 2 + ≈ 1.32 ( to 2 dec. places )
Answer:
[-20.25;+∞).
Step-by-step explanation:
1) according to the properties of the given parabola the minimum is:
2) y₀=-20.25 means, the value -20.25 is minimum of the range, the maximum →+∞;
3) finally, the range y≥-20.25.
This is solved by breaking the equasion down.
2 { 5 [12 + 5 (500 - 100) + 399 ]}
2 { 5 [12 + 5 (400) + 399]}
2 { 5 [12 + 2000 + 399]}
2 { 5 [2411]}
2 {12055}
24110
Is this the answer you were looking for?
So average is of the first 6 tests is 82 well that means
(test1 + test2+ test3+ test4 + test5+test6)/6 = 82
so now let do some cross multiplliying
test1 + test2 + test3 + test 4 + test5 +test6 = 82*6
test1 + test2 + test3 + test 4 + test5 +test6 = 492
now lets see if we can find that 7th test score
(test1 + test2 + test3 + test4 + test5 +test6 + test7)/7 = 80.5
So look we found test1 + test2 + test3 + test4 + test5 +test6 to be 492 so lets substitute.
(492 + test7 )/7 = 80.5
test7 = (80.5*7)-492 = 71.5
