Answer:1 (CIE 2012, s, paper 11, question 7)
The table shows values of variables
x
and
y
.
x
1
3
6
10
14
y
2.5
4.5
0
–
20
–
56
(i) By plotting a suitable straight line graph, show that
y
and
x
are related by the equation
y
=
A
x
+
B
x
2
,
where
A
and
B
are constants. [4]
(ii) Use your graph to find the value of
A
and of
B
.
[4]
2 (CIE 2012, s, paper 22, question 7)
The table shows experimental values of variables
x
and
y
.
x
5
30
150
400
y
8.9
21.9
48.9
80.6
(i) By plotting a suitable straight line graph, show that
y
and
x
are related by the equation
y
=
a
x
b
,
where
a
and
b
are constants. [4]
(ii) Use your graph to estimate the value of
a
and of
b
.
[4]
3 (CIE 2012, w, paper 11, question 10)
The table shows values of the variables
x
and
y
.
x
∘
10
30
45
60
80
y
11.2
16
19.5
22.4
24.7
(i) Using the graph paper below, plot a suitable straight line graph to show that, for 10°
≤
x
≤
80°,
√
y
=
A
sin
x
+
B
,
where
A
and
B
are positive constants. [4]
(ii) Use your graph to find the value of
A
and of
B
.
[3]
(iii) Estimate the value of
y
when
x
=
50.
[2]
(iv) Estimate the value of
x
when
y
=
12.
[2]
4 (CIE 2012, w, paper 22, question 8)
Explanation: