Answer:
Step-by-step explanation:
<u>Given quadratic function:</u>
<u>Points on the graph:</u>
- (-2,-35), (1,-5), (3,- 15)
<u>Substitute values of x and y and solve the system of equations:</u>
- -35 = a(-2)² + b(-2) + c ⇒ -35 = 4a - 2b + c ⇔ eq 1
- -5 = a(1)² + b(1) + c ⇒ -5 = a + b + c ⇔ eq 2
- -15 = a(3)² + b(3) + c ⇒ -15 = 9a + 3b + c ⇔ eq 3
<u>Subtract eq 2 from eq 1:</u>
- -35 - (-5) = 4a - 2b + c - a - b - c
- -30 = 3a - 3b
- b = a + 10 ⇔ eq 4
<u>Subtract eq 2 from eq 3:</u>
- -15 - (-5) = 9a + 3b + c - a - b - c
- -10 = 8a + 2b
- b = -4a - 5 ⇔ eq 5
<u>Compare eq 4 and eq 5, solve for a:</u>
- a + 10 = -4a - 5
- a + 4a = -5 - 10
- 5a = -15
- a = -3
<u>Find the value of b using eq 4:</u>
<u>Find the value of c using eq 2:</u>
- -5 = -3 + 7 + c
- c = -5 - 4
- c = -9
<u>We now have a, b and c:, the function is:</u>
Answer:
x = - 3, y = - 1
Step-by-step explanation:
y = 7x + 20 -----> equation 1
4x - y = - 11
4x - ( 7x + 20 ) = - 11
4x - 7x - 20 = - 11
- 3x = - 11 + 20
- 3x = 9
x = 9 / - 3
x = - 3
Substitute x = - 3 in equation 1,
y = 7 ( - 3 ) + 20
= - 21 + 20
y = - 1
Hence,
x = - 3
y = - 1
.4 is tenths .42 is hundredths and .422 is thousandths
Answer:
.6363 repeating
Step-by-step explanation:
