Foundation November 2019 Paper 1 Q24
24 The diagram shows triangle \(ABC\).
\(ADB\) is a straight line.
the size of angle \(DCB\) : the size of angle \(ACD = 2 : 1\)
Work out the size of angle \(BDC\). (4)
| Answer | Mark | Mark scheme |
|---|---|---|
| 93 | M1 | for method to find angle \(ACB\), eg \(180 - 75 - 51\ (= 54)\) |
| M1 | (dep M1) for method to use the ratio, eg \(\text{``}54\text{''} \div (2 + 1)\ (= 18)\) | |
| M1 | for complete method, eg \(180 - 51 - \text{``}18\text{''} \times 2\) or \(75 + \text{``}18\text{''}\) oe | |
| A1 | cao |
Additional guidance
Angles may be shown on diagram but must not be ambiguous
eg. M0 for angle of 54° shown in the wrong place